BACKGROUND Early renal artery thrombosis after kidney transplantation is rare but often leads to graft loss.Prompt diagnosis and intervention are essential,particularly in patients with inherited thrombophilias such a...BACKGROUND Early renal artery thrombosis after kidney transplantation is rare but often leads to graft loss.Prompt diagnosis and intervention are essential,particularly in patients with inherited thrombophilias such as factor V Leiden(FVL)mutation.CASE SUMMARY A kidney transplant recipient with FVL mutation developed an acute transplant renal artery thrombosis.The immediate post-operative Doppler ultrasonography revealed thrombosis of the main and inferior polar renal arteries.Emergent thrombectomy and separate arterial re-anastomoses were performed after cold perfusion with heparinized saline and vasodilator solution.Reperfusion was successful with immediate urine output and gradual improvement in renal function.The patient was discharged on direct oral anticoagulation therapy.CONCLUSION Early detection and surgical intervention can preserve graft function in posttransplant renal artery thrombosis even in patients at high risk.展开更多
BACKGROUND Kirsten rat sarcoma viral oncogene homolog(KRAS),neuroblastoma RAS viral oncogene homolog(NRAS),and v-raf murine sarcoma viral oncogene homolog B1(BRAF)nucleotide variants may generate quantitatively or qua...BACKGROUND Kirsten rat sarcoma viral oncogene homolog(KRAS),neuroblastoma RAS viral oncogene homolog(NRAS),and v-raf murine sarcoma viral oncogene homolog B1(BRAF)nucleotide variants may generate quantitatively or qualitatively various protein activities,which may be reflected in their differential association with tumor characteristics.AIM To examine the association between these mutations and colorectal cancer(CRC)progression stages.METHODS A retrospective analysis was conducted on 799 patients with CRC,whose tumor samples were examined for mutations in the hot-spots of the KRAS,NRAS,and BRAF genes at the University of Texas Medical Branch,spanning from January 2016 to July 2023.Statistical analyses were performed to assess the association of spe-cific nucleotide changes with tumor,nodes,and metastasis stages.RESULTS KRAS mutations were found in 39.5%of cases,NRAS mutations in 4.4%,and BRAF mutations in 6.0%.The KRAS p.Gly12Val and p.Gly13Asp mutations were positively associated with pathological stage 4 tumors.Additionally,the KRAS p.Gly12Asp and p.Gly12Val mutations were linked to an increased risk of distant metastasis.Meanwhile,the BRAF Val600Glu mutation was associated with a higher likelihood of lymph node involvement.CONCLUSION Our findings support the potential prognostic utility of specific KRAS(p.Gly12Val,p.Gly12Asp,and p.Gly13Asp)and BRAF p.Val600Glu mutations in CRC.These results are preliminary and require validation through larger,multi-center studies before they can be considered reliable in clinical practice.展开更多
In renewing tissues,mutations conferring selective advantage may result in clonal expansions1-4.In contrast to somatic tissues,mutations driving clonal expansions in spermatogonia(CES)are also transmitted to the next ...In renewing tissues,mutations conferring selective advantage may result in clonal expansions1-4.In contrast to somatic tissues,mutations driving clonal expansions in spermatogonia(CES)are also transmitted to the next generation.This results in an effective increase of de novo mutation rate for CES drivers5-8.CES was originally discovered through extreme recurrence of de novo mutations causing Apert syndrome5.Here,we develop a systematic approach to discover CES drivers as hotspots of human de novo mutation.Our analysis of 54,715 trios ascertained for rare conditions9-13,6,065 control trios12,14-19 and population variation from 807,162 mostly healthy individuals20 identifies genes manifesting rates of de novo mutations inconsistent with plausible models of disease ascertainment.We propose 23 genes hypermutable at loss-of-function(LoF)sites as candidate CES drivers.An extra 17 genes feature hypermutable missense mutations at individual positions,suggesting CES acting through gain of function.CES increases the average mutation rate roughly 17-fold for LoF genes in both control trios and sperm and roughly 500-fold for pooled gain-of-function sites in sperm21.Positive selection in the male germline elevates the prevalence of genetic disorders and increases polymorphism levels,masking the effect of negative selection in human populations.展开更多
BACKGROUND Only a few cases of diabetes mellitus with concurrent mutations in the mitochondrial MT-TL1 and CEL genes have been reported worldwide.Racial differences may influence mutation frequency,the presentation of...BACKGROUND Only a few cases of diabetes mellitus with concurrent mutations in the mitochondrial MT-TL1 and CEL genes have been reported worldwide.Racial differences may influence mutation frequency,the presentation of symptoms,and disease progression.This case report describes the clinical features,potential genetic mechanisms,and diagnostic complexity of young-onset diabetes mellitus with concurrent m.3243A>G mutation in MT-TL1 and c.1336G>A mutation in CEL.The objective is to inform precise typing,genetic counseling,and personalized treatment of monogenic diabetes mellitus,while expanding the evidence base on rare forms of diabetes mellitus.CASE SUMMARY A 30-year-old man,diagnosed with diabetic ketoacidosis six years earlier,presented with poor response to insulin therapy(glycated hemoglobin,15.35%),marked wasting(body mass index:15.06 kg/m2),sensorineural deafness,diabetic retinopathy,and peripheral neuropathy.Whole-exome sequencing revealed concurrent mutations:Mitochondrial MT-TL1 m.3243A>G(heteroplasmy 41.76%)and CEL c.1336G>A.Family investigation identified his mother,who also had diabetes,as a carrier of the CEL mutation,and his sister as harboring both mutations without diabetes.CONCLUSION This case highlights the genetic heterogeneity of monogenic diabetes and expands the known mutational spectrum.Comprehensive genetic testing is recommended to enhance diagnostic accuracy in cases of suspected monogenic diabetes.展开更多
BACKGROUND Although the relationship between somatic DNA polymerase epsilon(POLE)exonuclease domain mutations(EDMs)and colorectal cancer(CRC)is well established,the role of POLE non-EDMs in CRC remains unclear.AIM To ...BACKGROUND Although the relationship between somatic DNA polymerase epsilon(POLE)exonuclease domain mutations(EDMs)and colorectal cancer(CRC)is well established,the role of POLE non-EDMs in CRC remains unclear.AIM To identify POLE non-EDMs and EDMs in CRC,and to determine their associations with accompanying mutations and microsatellite instability(MSI).METHODS In this retrospective study,next-generation sequencing was performed using a targeted colon cancer panel(Qiagen,DHS-003Z)on 356 CRC patients.Of these,191 patients were found to carry POLE mutations.For these patients,MSI status was assessed using both real-time PCR(EasyPGX^(■)Ready MSI kit)and immunohistochemistry,and accompanying somatic mutations were investigated.RESULTS POLE mutations were identified in 53.65%of the CRC patients.Among the POLE-mutant patients,87.96%were classified as pMMR(MSI-L),and 12.04%as dMMR(MSI-H).The most frequently observed POLE non-EDM variant was exon 34 c.4337_4338delTG p.V1446fs*3.The POLE EDMs were present in exon 14,with two specific variants p.Y458F(0.52%)and p.Y468N(0.52%).The most common pathogenic variants accompanying the POLE mutations were in MLH3,MSH3,KRAS,PIK3CA,and BRAF genes.POLE mutations were associated with a high mutational burden and MSI in CRC,particularly in the dMMR phenotype.This association suggests that POLE mutations may serve as important biomarkers for understanding the genetic profile of the disease and may be used in the clinical management of CRC.CONCLUSION POLE mutations,especially non-EDMs,are frequent in MSI-L CRC and often co-occur with MLH3,MSH3,KRAS,PIK3CA,and BRAF,highlighting their potential role in tumor biology and as biomarkers for personalized treatment.Functional validation and multicenter studies are needed.展开更多
Inbreeding increases genome homozygosity within populations,which can exacerbate inbreeding depression by exposing homozygous deleterious alleles that are responsible for declines in fitness traits.In small population...Inbreeding increases genome homozygosity within populations,which can exacerbate inbreeding depression by exposing homozygous deleterious alleles that are responsible for declines in fitness traits.In small populations,genetic purging that occurs under the pressure of natural selection acts as an opposing force,contributing to a reduction of deleterious alleles.Both inbreeding and genetic purging are paramount in the field of conservation genomics.The Amur tiger(Panthera tigris altaica)lives in small populations in the forests of Northeast Asia and is among the most endangered animals on the planet.Using genome-wide assessment and comparison,we reveal substantially higher and more extensive inbreeding in wild Amur tigers(F_(ROH)=0.50)than in captive individuals(F_(ROH)=0.24).However,a relatively reduced number of lossof-function mutations in wild Amur tigers is observed compared to captive individuals,indicating genetic purging of inbreeding load with relatively large-effect alleles.The higher ratio of homozygous mutation load and number of fixed damaging alleles in the wild population indicates a less-efficient genetic purging,with purifying selection also contributing to this process.These findings provide valuable insights for the future conservation of Amur tigers.展开更多
Certain amino acids changes in the human Na^(+)/K^(+)-ATPase pump,ATPase Na^(+)/K^(+)transporting subunit alpha 1(ATP1A1),cause Charcot-Marie-Tooth disease type 2(CMT2)disease and refractory seizures.To develop in viv...Certain amino acids changes in the human Na^(+)/K^(+)-ATPase pump,ATPase Na^(+)/K^(+)transporting subunit alpha 1(ATP1A1),cause Charcot-Marie-Tooth disease type 2(CMT2)disease and refractory seizures.To develop in vivo models to study the role of Na^(+)/K^(+)-ATPase in these diseases,we modified the Drosophila gene homolog,Atpα,to mimic the human ATP1A1 gene mutations that cause CMT2.Mutations located within the helical linker region of human ATP1A1(I592T,A597T,P600T,and D601F)were simultaneously introduced into endogenous Drosophila Atpαby CRISPR/Cas9-mediated genome editing,generating the Atpα^(TTTF)model.In addition,the same strategy was used to generate the corresponding single point mutations in flies(Atpα^(I571T),Atpα^(A576T),Atpα^(P579T),and Atpα^(D580F)).Moreover,a deletion mutation(Atpα^(mut))that causes premature termination of translation was generated as a positive control.Of these alleles,we found two that could be maintained as homozygotes(Atpα^(I571T)and Atpα^(P579T)).Three alleles(Atpα^(A576T),Atpα^(P579)and Atpα^(D580F))can form heterozygotes with the Atpαmut allele.We found that the Atpαallele carrying these CMT2-associated mutations showed differential phenotypes in Drosophila.Flies heterozygous for Atpα^(TTTF)mutations have motor performance defects,a reduced lifespan,seizures,and an abnormal neuronal morphology.These Drosophila models will provide a new platform for studying the function and regulation of the sodium-potassium pump.展开更多
BACKGROUND Thrombophilia contributes to a significant increased risk of venous thromboembolism and can be either inherited or acquired.Hereditary thrombophilia may arise from various gene mutations,some of which have ...BACKGROUND Thrombophilia contributes to a significant increased risk of venous thromboembolism and can be either inherited or acquired.Hereditary thrombophilia may arise from various gene mutations,some of which have not even been adequately reported or poorly understood.Previous studies reported a rare and novel missense mutation in the prothrombin gene(p.Arg596Gln),known as prothrombin Belgrade.The mechanisms and therapeutic strategies associated with prothrombin Belgrade mutation have not been fully elucidated.CASE SUMMARY We present the case of a 26-year-old woman with recurrent systemic thrombosis induced by prothrombin Belgrade mutation.The patient suffered from cerebral venous sinus thrombosis that rapidly progressed to systemic thrombosis,alongside a family history of cerebral thrombosis,and no traditional risk factors or abnormal coagulation function.Whole-genome sequencing detected a novel and rare heterozygous prothrombin missense mutation,c.1787G>T(p.Arg596Gln),which was responsible for the major etiology of the systemic thrombosis.CONCLUSION This case strengthens our understanding about hereditary basis of thrombophilia and provokes considerations for therapeutic options on prothrombin Belgrade mutation.展开更多
Sotos syndrome is characterized by overgrowth features and is caused by alterations in the nuclear receptor binding SET domain protein 1 gene.Attentiondeficit/hyperactivity disorder(ADHD)is considered a neurodevelopme...Sotos syndrome is characterized by overgrowth features and is caused by alterations in the nuclear receptor binding SET domain protein 1 gene.Attentiondeficit/hyperactivity disorder(ADHD)is considered a neurodevelopment and psychiatric disorder in childhood.Genetic characteristics and clinical presentation could play an important role in the diagnosis of Sotos syndrome and ADHD.Magnetic resonance imaging(MRI)has been used to assess medical images in Sotos syndrome and ADHD.The images process is considered to display in MRI while wavelet fusion has been used to integrate distinct images for achieving more complete information in single image in this editorial.In the future,genetic mechanisms and artificial intelligence related to medical images could be used in the clinical diagnosis of Sotos syndrome and ADHD.展开更多
BACKGROUND Through deeper understanding of targetable driver mutations in non-small-cell lung cancer(NSCLC)over the past years,some patients with driver mutations have benefited from the targeted molecular therapies.A...BACKGROUND Through deeper understanding of targetable driver mutations in non-small-cell lung cancer(NSCLC)over the past years,some patients with driver mutations have benefited from the targeted molecular therapies.Although the anaplastic lymphoma kinase and BRAF mutations are not frequent subtypes in NSCLC,the availability of several targeted-drugs has been confirmed through a series of clinical trials.But little is clear about the proper strategy in rare BRAF G469A mutation,not to mention co-exhibition of anaplastic lymphoma kinase and BRAF G469A mutations,which is extremely rare in NSCLC.CASE SUMMARY We present a patient to stage IVA lung adenocarcinoma with coexisting echinoderm microtubule associated protein like-4 rearrangement and BRAF G469A mutation.She received several targeted drugs with unintended resistance and suffered from unbearable adverse events.CONCLUSION Due to the rarity of co-mutations,the case not only enriches the limited literature on NSCLC harbouring BRAF G469A and echinoderm microtubule associated protein like-4 mutations,but also suggests the efficacy and safety of specific multiple-drug therapy in such patients.展开更多
Objective:Keratoconus(KC)is a progressive corneal ectasia disorder,arising from a myriad of causes including genetic predispositions,environmental factors,biomechanical influences,and inflammatory reactions.This study...Objective:Keratoconus(KC)is a progressive corneal ectasia disorder,arising from a myriad of causes including genetic predispositions,environmental factors,biomechanical influences,and inflammatory reactions.This study aims to identify potential pathogenetic gene mutations in patients with sporadic KC in the Han Chinese population.Methods:Twenty-five patients with primary KC as well as 50 unrelated population matched healthy controls,were included in this study to identify potential pathogenic gene mutations among sporadic KC patients in the Han Chinese population.Sanger sequencing and whole-exome sequencing(WES)were used to analyze mutations in the zinc finger protein 469(ZNF469)gene.Bioinformatics analysis was conducted to explore the potential role of ZNF469 in KC pathogenesis.Results:Five novel heterozygous missense variants were identified in KC patients.Among them,2 compound heterozygous variants,c.8986G>C(p.E2996Q)with c.11765A>C(p.D3922A),and c.4423C>G(p.L1475V)with c.10633G>A(p.G3545R),were determined to be possible pathogenic factors for KC.Conclusion:Mutations in the ZNF469 gene may contribute to the development of KC in the Han Chinese population.These mutation sites may provide valuable information for future genetic screening of KC patients and their families.展开更多
Single-stranded DNA-binding proteins(SSBs)play essential roles in the replication,recombination and repair processes of organellar DNA molecules.In Arabidopsis thaliana,SSBs are encoded by a small family of two genes(...Single-stranded DNA-binding proteins(SSBs)play essential roles in the replication,recombination and repair processes of organellar DNA molecules.In Arabidopsis thaliana,SSBs are encoded by a small family of two genes(SSB1 and SSB2).However,the functional divergence of these two SSB copies in plants remains largely unknown,and detailed studies regarding their roles in the replication and recombination of organellar genomes are still incomplete.In this study,phylogenetic,gene structure and protein motif analyses all suggested that SSB1 and SSB2 probably diverged during the early evolution of seed plants.Based on accurate long-read sequencing results,ssb1 and ssb2 mutants had decreased copy numbers for both mitochondrial DNA(mtDNA)and plastid DNA(ptDNA),accompanied by a slight increase in structural rearrangements mediated by intermediate-sized repeats in mt genome and small-scale variants in both genomes.Our findings provide an important foundation for further investigating the effects of DNA dosage in the regulation of mutation frequencies in plant organellar genomes.展开更多
BACKGROUND Recurrence remains the leading cause of poor prognosis in hepatocellular carcinoma(HCC),particularly among patients infected with hepatitis B virus(HBV).The telomerase reverse transcriptase(TERT)promoter is...BACKGROUND Recurrence remains the leading cause of poor prognosis in hepatocellular carcinoma(HCC),particularly among patients infected with hepatitis B virus(HBV).The telomerase reverse transcriptase(TERT)promoter is the most frequently mutated site in HBV-related HCC;however,its prognostic significance is not fully established.AIM To evaluate the prognostic impact of TERT promoter mutations and efficiency of digital polymerase chain reaction(dPCR).METHODS A total of 66 HBV-related HCC patients who underwent hepatectomy were enrolled in this study.DNA extracted from fresh tumor tissues was analyzed for TERT promoter mutations using Sanger sequencing and dPCR.The dPCR assay was optimized by adding 7-deaza-dGTP,CviQ1,and ethylenediaminetetraacetic acid to improve detection sensitivity.Concordance between methods was assessed,and nomogram survival prediction models were developed to evaluate prognostic value based on mutation status.RESULTS TERT promoter mutations were detected in 26/66(39.39%)cases by Sanger sequencing and 30/66(45.45%)by dPCR.The two methods showed high concordance(93.939%,κ=0.876),with dPCR demonstrating 100%sensitivity and 90%specificity.Patients harboring TERT promoter mutations exhibited reduced overall survival and higher recurrence risk.Nomogram models successfully distinguished mutant from non-mutant cases for both overall survival(C-index:0.7651)and disease-free survival(C-index:0.6899).CONCLUSION TERT promoter mutation predicts poor prognosis in HBV-related HCC and serves as a biomarker for risk stratification.Optimized dPCR outperforms Sanger sequencing,and nomograms with TERT status guide precision therapy.展开更多
The use of RNA interference(RNAi)technology to control pests is explored by researchers globally.Even though RNA is a new class of pest control compound unlike conventional chemical pesticides,the evolution of pest re...The use of RNA interference(RNAi)technology to control pests is explored by researchers globally.Even though RNA is a new class of pest control compound unlike conventional chemical pesticides,the evolution of pest resistance needs to be considered.Here,we first investigate RNAi-based biopesticide resistance of Fusarium asiaticum,which is responsible for devastating diseases of plants,for example,Fusarium head blight.Five resistant strains were isolated from 500 strains that treated with UV-mutagenesis.The mutation common to all of the five resistant mutants occurred in the gene encoding Dicer2(point mutations at codon 1005 and 1007),which were under strong purifying selection pressure.To confirm whether the mutations in Dicer2 confer resistance to RNAi,we exchanged the Dicer2 locus between the sensitive strain and the resistant strain by homologous double exchange.The transformed mutants,Dicer2^(R1005D)and Dicer2^(E1007H),exhibited resistance to dsRNA in vitro.Further study showed that mutations of R1005D and E1007H affected the intramolecular interactions of Dicer2,resulting in the dysfunction of RNase III domain of Dicer2.The amount of sRNAs produced by Dicer2^(R1005D)and Dicer2^(E1007H)was extremely reduced along with variation of sRNA length.Together,these findings revealed a new potential mechanism of RNAi resistance and provided insight into RNAi-related biopesticide deployment for fungal control.展开更多
Objective:To investigate the clinical and molecular genetic characteristics of Chinese adolescents with maturity-onset diabetes of the young type 2(MODY 2)and the safety and efficacy of recombinant human growth hormon...Objective:To investigate the clinical and molecular genetic characteristics of Chinese adolescents with maturity-onset diabetes of the young type 2(MODY 2)and the safety and efficacy of recombinant human growth hormone(r-hGH).Methods:The clinical features and laboratory data of a family with MODY 2 combined with partial growth hormone deficiency(pGHD),diagnosed at the Fourth Clinical Medical College of Xinjiang Medical University,were analyzed.DNA was extracted from peripheral blood using the column method,and Sanger sequencing was conducted to analyze the glucokinase(GCK),hepatocyte nuclear factor 1α(HNF1α),and hepatocyte nuclear factor 4α(HNF4α)in the proband and relevant family members.Results:A heterozygous mutation in GCK(Reference sequence:NM_000162,location:Exon 10)c.1340G>A(p.R447Q)was detected in three family members(the proband,the proband’s younger brother,and their mother).The proband also had pGHD.Conclusion:GCK mutations causing MODY 2 exist in the Chinese population,and the combined treatment with r-hGH is safe and effective.展开更多
Chronic pancreatitis(CP)is a progressive and irreversible fibroinflammatory disease that markedly increases susceptibility to pancreatic cancer and remains without effective targeted therapies.Among the genetic contri...Chronic pancreatitis(CP)is a progressive and irreversible fibroinflammatory disease that markedly increases susceptibility to pancreatic cancer and remains without effective targeted therapies.Among the genetic contributors to CP,the carboxypeptidase A1 p.Ser282Pro(CPA1^(S282P))variant has been proposed to promote disease through misfolding-induced endoplasmic reticulum stress(ERS),although the broader pathogenic landscape remains incompletely defined.This study generated a rabbit model mimicking the human CPA1S282P mutation using the SpRY-ABE-8.17 system.Homozygous CPA1^(S282P)rabbits exhibited characteristic human CP phenotypes following alcohol induction,including visceral pain,elevated serum lipase and amylase,inflammatory cell infiltration,and extensive pancreatic fibrosis.Biochemical analyses confirmed that the p.S282P mutation induced CPA1 misfolding and elevated the expression of ERS markers GRP78 and CHOP in both transfected HEK293T cells and homozygous mutant rabbits.Notably,the CPA1^(S282P)mutation markedly disrupted intra-pancreatic lipid homeostasis,contributing to the development of CP in mutant rabbits.This study successfully established the first rabbit model of CP that accurately recapitulates CP caused by a defined human point mutation.Additionally,this study provides insights into a previously unrecognized link between CPA1 and intra-pancreatic lipid metabolism,offering a foundation for identifying novel therapeutic targets for human CP.展开更多
Starch biosynthesis is a complex process that relies on the coordinated action of multiple enzymes.Resistant starch is not digested in the small intestine,thus preventing a rapid rise in the glycemic index.Starch synt...Starch biosynthesis is a complex process that relies on the coordinated action of multiple enzymes.Resistant starch is not digested in the small intestine,thus preventing a rapid rise in the glycemic index.Starch synthase 2a(SS2a)is a key enzyme in amylopectin biosynthesis that has significant effects on starch structure and properties.In this study,we identified an ss2a null mutant(M3-1413)with a single base mutation from an ethyl methane sulfonate(EMS)-mutagenized population of barley.The mutation was located at the 3'end of the first intron of the RNA splicing receptor(AG)site,and resulted in abnormal RNA splicing and two abnormal transcripts of ss2a,which caused the inactivation of the SS2a gene.The starch structure and properties were significantly altered in the mutant,with M3-1413 containing lower total starch and higher amylose and resistant starch levels.This study sheds light on the effect of barley ss2a null mutations on starch properties and will help to guide new applications of barley starch in the development of nutritious food products.展开更多
The CRISPR/Cas9 system has shown great promise in engineering targeted mutations in a genome.The efficiency of Cas9-mediated genome editing is temperature sensitive.A high-temperature regime can increase the mutation ...The CRISPR/Cas9 system has shown great promise in engineering targeted mutations in a genome.The efficiency of Cas9-mediated genome editing is temperature sensitive.A high-temperature regime can increase the mutation efficiency induced by the CRISPR/Cas9 system in many plant species.However,a heat stress treatment has not been applied during the tissue culture process in citrus.To develop an efficient heat stress regime to improve the efficiency of CRISPR/Cas9-mediated targeted mutagenesis,three and five cycles of heat stress treatments were used during callus induction in citrus.The results showed that the heat stress treatment with three cycles of 24 h at 37℃,followed by 24 h at 26℃,increased the mutation efficiency by 11.6%compared with no heat stress treatment,and that five cycles of heat stress treatment were optimal,from which 50%mutants had a 100%mutation rate.The mutation profiles of Cas9 at 28℃ for 10 d and 37℃ for three or five cycles were similar,indicating that heat stress treatment did not affect the non-homologous end joining repair pathway.No detectable off-target mutation was detected in the potential off-target sites with four nucleotide mismatches compared with the designed on-target site.This study demonstrated that five cycles of heat stress treatment during callus induction could efficiently increase the mutation efficiency mediated by the CRISPR/Cas9 system without observable negative effects,and provided an efficient Cas9-mediated citrus genome editing system to produce mutants with a high mutation rate.展开更多
BACKGROUND Familial adenomatous polyposis(FAP)is an autosomal dominant syndrome that results from a germline mutation in the adenomatous polyposis coli gene.It is characterized by the early development of hundreds of ...BACKGROUND Familial adenomatous polyposis(FAP)is an autosomal dominant syndrome that results from a germline mutation in the adenomatous polyposis coli gene.It is characterized by the early development of hundreds of adenomas in the colon during the second decade of life.If prophylactic colectomy is not performed,most patients eventually develop colorectal cancer(CRC).CASE SUMMARY We present the mutational profile of a case of FAP that progressed to CRC.A 45-year-old Saudi man presented with intestinal obstruction and underwent a total colectomy.The colon showed hundreds of polyps and two infiltrative ulcerative lesions,which proved to be adenocarcinoma according to histopathology.We performed next-generation sequencing and found mutations in the TP53,NRAS,EGFR PDGFR,MET,KIT,ERBB2,and GUSP genes.CONCLUSION To the best of our knowledge,this case report is the first to sheds the light on the mutation profile of FAP that progressed to CRC in Saudi Arabia.展开更多
BACKGROUND Pancreatic cancer(PC)is a highly malignant tumor that is resistant to chemotherapy,radiotherapy and immunotherapy.Combination chemotherapy regimens are the standard first-line regimens for metastatic diseas...BACKGROUND Pancreatic cancer(PC)is a highly malignant tumor that is resistant to chemotherapy,radiotherapy and immunotherapy.Combination chemotherapy regimens are the standard first-line regimens for metastatic disease,with a median survival<12 months.Although recurrent genomic alterations such as the BRAF V600E mutation have been reported in PC,evidence supporting the clinical effectiveness of molecularly guided targeted therapies is limited.CASE SUMMARY We report a case of a 33-year-old male who was referred to our department with weight loss of 5 kg in 2 months,anorexia and abdominal pain.Imaging showed extensive lesions involving the pancreas,liver,bones,muscles and lymph nodes accompanied by elevated carbohydrate antigen 19-9(CA19-9)and carcinoembryonic antigen(CEA).Biopsy yielded a diagnosis of PC.Treatment with gemcitabine and nab-paclitaxel was initiated,but the disease progressed in<2 months even though the patient’s general condition improved.Molecular testing revealed the presence of BRAF mutation.Dabrafenib/trametinib combination therapy was introduced,and the patient was treated for 2 months with a decrease in CA19-9 and CEA levels,but he died after 2 months of treatment.CONCLUSION BRAF alterations are infrequent in PC.This case highlights the significance of molecular profiling in patients with PC,especially in patients with a high tumor burden.展开更多
文摘BACKGROUND Early renal artery thrombosis after kidney transplantation is rare but often leads to graft loss.Prompt diagnosis and intervention are essential,particularly in patients with inherited thrombophilias such as factor V Leiden(FVL)mutation.CASE SUMMARY A kidney transplant recipient with FVL mutation developed an acute transplant renal artery thrombosis.The immediate post-operative Doppler ultrasonography revealed thrombosis of the main and inferior polar renal arteries.Emergent thrombectomy and separate arterial re-anastomoses were performed after cold perfusion with heparinized saline and vasodilator solution.Reperfusion was successful with immediate urine output and gradual improvement in renal function.The patient was discharged on direct oral anticoagulation therapy.CONCLUSION Early detection and surgical intervention can preserve graft function in posttransplant renal artery thrombosis even in patients at high risk.
文摘BACKGROUND Kirsten rat sarcoma viral oncogene homolog(KRAS),neuroblastoma RAS viral oncogene homolog(NRAS),and v-raf murine sarcoma viral oncogene homolog B1(BRAF)nucleotide variants may generate quantitatively or qualitatively various protein activities,which may be reflected in their differential association with tumor characteristics.AIM To examine the association between these mutations and colorectal cancer(CRC)progression stages.METHODS A retrospective analysis was conducted on 799 patients with CRC,whose tumor samples were examined for mutations in the hot-spots of the KRAS,NRAS,and BRAF genes at the University of Texas Medical Branch,spanning from January 2016 to July 2023.Statistical analyses were performed to assess the association of spe-cific nucleotide changes with tumor,nodes,and metastasis stages.RESULTS KRAS mutations were found in 39.5%of cases,NRAS mutations in 4.4%,and BRAF mutations in 6.0%.The KRAS p.Gly12Val and p.Gly13Asp mutations were positively associated with pathological stage 4 tumors.Additionally,the KRAS p.Gly12Asp and p.Gly12Val mutations were linked to an increased risk of distant metastasis.Meanwhile,the BRAF Val600Glu mutation was associated with a higher likelihood of lymph node involvement.CONCLUSION Our findings support the potential prognostic utility of specific KRAS(p.Gly12Val,p.Gly12Asp,and p.Gly13Asp)and BRAF p.Val600Glu mutations in CRC.These results are preliminary and require validation through larger,multi-center studies before they can be considered reliable in clinical practice.
文摘In renewing tissues,mutations conferring selective advantage may result in clonal expansions1-4.In contrast to somatic tissues,mutations driving clonal expansions in spermatogonia(CES)are also transmitted to the next generation.This results in an effective increase of de novo mutation rate for CES drivers5-8.CES was originally discovered through extreme recurrence of de novo mutations causing Apert syndrome5.Here,we develop a systematic approach to discover CES drivers as hotspots of human de novo mutation.Our analysis of 54,715 trios ascertained for rare conditions9-13,6,065 control trios12,14-19 and population variation from 807,162 mostly healthy individuals20 identifies genes manifesting rates of de novo mutations inconsistent with plausible models of disease ascertainment.We propose 23 genes hypermutable at loss-of-function(LoF)sites as candidate CES drivers.An extra 17 genes feature hypermutable missense mutations at individual positions,suggesting CES acting through gain of function.CES increases the average mutation rate roughly 17-fold for LoF genes in both control trios and sperm and roughly 500-fold for pooled gain-of-function sites in sperm21.Positive selection in the male germline elevates the prevalence of genetic disorders and increases polymorphism levels,masking the effect of negative selection in human populations.
基金Supported by Jilin Province Science and Technology Development Project,No.20220203018SF。
文摘BACKGROUND Only a few cases of diabetes mellitus with concurrent mutations in the mitochondrial MT-TL1 and CEL genes have been reported worldwide.Racial differences may influence mutation frequency,the presentation of symptoms,and disease progression.This case report describes the clinical features,potential genetic mechanisms,and diagnostic complexity of young-onset diabetes mellitus with concurrent m.3243A>G mutation in MT-TL1 and c.1336G>A mutation in CEL.The objective is to inform precise typing,genetic counseling,and personalized treatment of monogenic diabetes mellitus,while expanding the evidence base on rare forms of diabetes mellitus.CASE SUMMARY A 30-year-old man,diagnosed with diabetic ketoacidosis six years earlier,presented with poor response to insulin therapy(glycated hemoglobin,15.35%),marked wasting(body mass index:15.06 kg/m2),sensorineural deafness,diabetic retinopathy,and peripheral neuropathy.Whole-exome sequencing revealed concurrent mutations:Mitochondrial MT-TL1 m.3243A>G(heteroplasmy 41.76%)and CEL c.1336G>A.Family investigation identified his mother,who also had diabetes,as a carrier of the CEL mutation,and his sister as harboring both mutations without diabetes.CONCLUSION This case highlights the genetic heterogeneity of monogenic diabetes and expands the known mutational spectrum.Comprehensive genetic testing is recommended to enhance diagnostic accuracy in cases of suspected monogenic diabetes.
文摘BACKGROUND Although the relationship between somatic DNA polymerase epsilon(POLE)exonuclease domain mutations(EDMs)and colorectal cancer(CRC)is well established,the role of POLE non-EDMs in CRC remains unclear.AIM To identify POLE non-EDMs and EDMs in CRC,and to determine their associations with accompanying mutations and microsatellite instability(MSI).METHODS In this retrospective study,next-generation sequencing was performed using a targeted colon cancer panel(Qiagen,DHS-003Z)on 356 CRC patients.Of these,191 patients were found to carry POLE mutations.For these patients,MSI status was assessed using both real-time PCR(EasyPGX^(■)Ready MSI kit)and immunohistochemistry,and accompanying somatic mutations were investigated.RESULTS POLE mutations were identified in 53.65%of the CRC patients.Among the POLE-mutant patients,87.96%were classified as pMMR(MSI-L),and 12.04%as dMMR(MSI-H).The most frequently observed POLE non-EDM variant was exon 34 c.4337_4338delTG p.V1446fs*3.The POLE EDMs were present in exon 14,with two specific variants p.Y458F(0.52%)and p.Y468N(0.52%).The most common pathogenic variants accompanying the POLE mutations were in MLH3,MSH3,KRAS,PIK3CA,and BRAF genes.POLE mutations were associated with a high mutational burden and MSI in CRC,particularly in the dMMR phenotype.This association suggests that POLE mutations may serve as important biomarkers for understanding the genetic profile of the disease and may be used in the clinical management of CRC.CONCLUSION POLE mutations,especially non-EDMs,are frequent in MSI-L CRC and often co-occur with MLH3,MSH3,KRAS,PIK3CA,and BRAF,highlighting their potential role in tumor biology and as biomarkers for personalized treatment.Functional validation and multicenter studies are needed.
基金supported by the Fundamental Research Funds for the Central Universities of China(2572022DQ03)the National Natural Science Foundation of China(32170517)+2 种基金the Guangdong Provincial Key Laboratory of Genome Read and Write(2017B030301011)the Start-up Scientific Foundation of Northeast Forestry University(60201524043)supported by China National GeneBank(CNGB).
文摘Inbreeding increases genome homozygosity within populations,which can exacerbate inbreeding depression by exposing homozygous deleterious alleles that are responsible for declines in fitness traits.In small populations,genetic purging that occurs under the pressure of natural selection acts as an opposing force,contributing to a reduction of deleterious alleles.Both inbreeding and genetic purging are paramount in the field of conservation genomics.The Amur tiger(Panthera tigris altaica)lives in small populations in the forests of Northeast Asia and is among the most endangered animals on the planet.Using genome-wide assessment and comparison,we reveal substantially higher and more extensive inbreeding in wild Amur tigers(F_(ROH)=0.50)than in captive individuals(F_(ROH)=0.24).However,a relatively reduced number of lossof-function mutations in wild Amur tigers is observed compared to captive individuals,indicating genetic purging of inbreeding load with relatively large-effect alleles.The higher ratio of homozygous mutation load and number of fixed damaging alleles in the wild population indicates a less-efficient genetic purging,with purifying selection also contributing to this process.These findings provide valuable insights for the future conservation of Amur tigers.
基金supported by the Natural Science Foundation of Fujian Province,No.2020J02027the National Natural Science Foundation of China,No.31970461the Foundation of NHC Key Laboratory of Technical Evaluation of Fertility Regulation for Non-human Primate,Fujian Maternity and Child Health Hospital,No.2022-NHP-05(all to WC).
文摘Certain amino acids changes in the human Na^(+)/K^(+)-ATPase pump,ATPase Na^(+)/K^(+)transporting subunit alpha 1(ATP1A1),cause Charcot-Marie-Tooth disease type 2(CMT2)disease and refractory seizures.To develop in vivo models to study the role of Na^(+)/K^(+)-ATPase in these diseases,we modified the Drosophila gene homolog,Atpα,to mimic the human ATP1A1 gene mutations that cause CMT2.Mutations located within the helical linker region of human ATP1A1(I592T,A597T,P600T,and D601F)were simultaneously introduced into endogenous Drosophila Atpαby CRISPR/Cas9-mediated genome editing,generating the Atpα^(TTTF)model.In addition,the same strategy was used to generate the corresponding single point mutations in flies(Atpα^(I571T),Atpα^(A576T),Atpα^(P579T),and Atpα^(D580F)).Moreover,a deletion mutation(Atpα^(mut))that causes premature termination of translation was generated as a positive control.Of these alleles,we found two that could be maintained as homozygotes(Atpα^(I571T)and Atpα^(P579T)).Three alleles(Atpα^(A576T),Atpα^(P579)and Atpα^(D580F))can form heterozygotes with the Atpαmut allele.We found that the Atpαallele carrying these CMT2-associated mutations showed differential phenotypes in Drosophila.Flies heterozygous for Atpα^(TTTF)mutations have motor performance defects,a reduced lifespan,seizures,and an abnormal neuronal morphology.These Drosophila models will provide a new platform for studying the function and regulation of the sodium-potassium pump.
文摘BACKGROUND Thrombophilia contributes to a significant increased risk of venous thromboembolism and can be either inherited or acquired.Hereditary thrombophilia may arise from various gene mutations,some of which have not even been adequately reported or poorly understood.Previous studies reported a rare and novel missense mutation in the prothrombin gene(p.Arg596Gln),known as prothrombin Belgrade.The mechanisms and therapeutic strategies associated with prothrombin Belgrade mutation have not been fully elucidated.CASE SUMMARY We present the case of a 26-year-old woman with recurrent systemic thrombosis induced by prothrombin Belgrade mutation.The patient suffered from cerebral venous sinus thrombosis that rapidly progressed to systemic thrombosis,alongside a family history of cerebral thrombosis,and no traditional risk factors or abnormal coagulation function.Whole-genome sequencing detected a novel and rare heterozygous prothrombin missense mutation,c.1787G>T(p.Arg596Gln),which was responsible for the major etiology of the systemic thrombosis.CONCLUSION This case strengthens our understanding about hereditary basis of thrombophilia and provokes considerations for therapeutic options on prothrombin Belgrade mutation.
基金Supported by Natural Science Foundation of Shanghai,No.17ZR1431400National Key R and D Program of China,No.2017YFA0103902.
文摘Sotos syndrome is characterized by overgrowth features and is caused by alterations in the nuclear receptor binding SET domain protein 1 gene.Attentiondeficit/hyperactivity disorder(ADHD)is considered a neurodevelopment and psychiatric disorder in childhood.Genetic characteristics and clinical presentation could play an important role in the diagnosis of Sotos syndrome and ADHD.Magnetic resonance imaging(MRI)has been used to assess medical images in Sotos syndrome and ADHD.The images process is considered to display in MRI while wavelet fusion has been used to integrate distinct images for achieving more complete information in single image in this editorial.In the future,genetic mechanisms and artificial intelligence related to medical images could be used in the clinical diagnosis of Sotos syndrome and ADHD.
基金Supported by the Medical Education Collaborative Innovation Fund of Jiangsu University,No.JDY2022015。
文摘BACKGROUND Through deeper understanding of targetable driver mutations in non-small-cell lung cancer(NSCLC)over the past years,some patients with driver mutations have benefited from the targeted molecular therapies.Although the anaplastic lymphoma kinase and BRAF mutations are not frequent subtypes in NSCLC,the availability of several targeted-drugs has been confirmed through a series of clinical trials.But little is clear about the proper strategy in rare BRAF G469A mutation,not to mention co-exhibition of anaplastic lymphoma kinase and BRAF G469A mutations,which is extremely rare in NSCLC.CASE SUMMARY We present a patient to stage IVA lung adenocarcinoma with coexisting echinoderm microtubule associated protein like-4 rearrangement and BRAF G469A mutation.She received several targeted drugs with unintended resistance and suffered from unbearable adverse events.CONCLUSION Due to the rarity of co-mutations,the case not only enriches the limited literature on NSCLC harbouring BRAF G469A and echinoderm microtubule associated protein like-4 mutations,but also suggests the efficacy and safety of specific multiple-drug therapy in such patients.
基金supported by the National Natural Science Foundation(82271057)the Natural Science Foundation of Hunan Province(2023JJ30818),China。
文摘Objective:Keratoconus(KC)is a progressive corneal ectasia disorder,arising from a myriad of causes including genetic predispositions,environmental factors,biomechanical influences,and inflammatory reactions.This study aims to identify potential pathogenetic gene mutations in patients with sporadic KC in the Han Chinese population.Methods:Twenty-five patients with primary KC as well as 50 unrelated population matched healthy controls,were included in this study to identify potential pathogenic gene mutations among sporadic KC patients in the Han Chinese population.Sanger sequencing and whole-exome sequencing(WES)were used to analyze mutations in the zinc finger protein 469(ZNF469)gene.Bioinformatics analysis was conducted to explore the potential role of ZNF469 in KC pathogenesis.Results:Five novel heterozygous missense variants were identified in KC patients.Among them,2 compound heterozygous variants,c.8986G>C(p.E2996Q)with c.11765A>C(p.D3922A),and c.4423C>G(p.L1475V)with c.10633G>A(p.G3545R),were determined to be possible pathogenic factors for KC.Conclusion:Mutations in the ZNF469 gene may contribute to the development of KC in the Han Chinese population.These mutation sites may provide valuable information for future genetic screening of KC patients and their families.
基金supported by grants from the National Natural Science Foundation of China(32170238,32400191)Guangdong Basic and Applied Basic Research Foundation(2023A1515111029)+2 种基金the Science,Technology and Innovation Commission of Shenzhen Municipality(RCYX20200714114538196)the Chinese Academy of Agricultural Sciences Elite Youth Program(grant 110243160001007)the Guangdong Pearl River Talent Program(2021QN02N792)。
文摘Single-stranded DNA-binding proteins(SSBs)play essential roles in the replication,recombination and repair processes of organellar DNA molecules.In Arabidopsis thaliana,SSBs are encoded by a small family of two genes(SSB1 and SSB2).However,the functional divergence of these two SSB copies in plants remains largely unknown,and detailed studies regarding their roles in the replication and recombination of organellar genomes are still incomplete.In this study,phylogenetic,gene structure and protein motif analyses all suggested that SSB1 and SSB2 probably diverged during the early evolution of seed plants.Based on accurate long-read sequencing results,ssb1 and ssb2 mutants had decreased copy numbers for both mitochondrial DNA(mtDNA)and plastid DNA(ptDNA),accompanied by a slight increase in structural rearrangements mediated by intermediate-sized repeats in mt genome and small-scale variants in both genomes.Our findings provide an important foundation for further investigating the effects of DNA dosage in the regulation of mutation frequencies in plant organellar genomes.
基金Supported by National Key Research and Development Program of China,No.2023YFF0613304Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences,No.2023-I2M-2-004,No.2024-I2M-C&T-B-069,and No.2025-I2M-C&T-B-057.
文摘BACKGROUND Recurrence remains the leading cause of poor prognosis in hepatocellular carcinoma(HCC),particularly among patients infected with hepatitis B virus(HBV).The telomerase reverse transcriptase(TERT)promoter is the most frequently mutated site in HBV-related HCC;however,its prognostic significance is not fully established.AIM To evaluate the prognostic impact of TERT promoter mutations and efficiency of digital polymerase chain reaction(dPCR).METHODS A total of 66 HBV-related HCC patients who underwent hepatectomy were enrolled in this study.DNA extracted from fresh tumor tissues was analyzed for TERT promoter mutations using Sanger sequencing and dPCR.The dPCR assay was optimized by adding 7-deaza-dGTP,CviQ1,and ethylenediaminetetraacetic acid to improve detection sensitivity.Concordance between methods was assessed,and nomogram survival prediction models were developed to evaluate prognostic value based on mutation status.RESULTS TERT promoter mutations were detected in 26/66(39.39%)cases by Sanger sequencing and 30/66(45.45%)by dPCR.The two methods showed high concordance(93.939%,κ=0.876),with dPCR demonstrating 100%sensitivity and 90%specificity.Patients harboring TERT promoter mutations exhibited reduced overall survival and higher recurrence risk.Nomogram models successfully distinguished mutant from non-mutant cases for both overall survival(C-index:0.7651)and disease-free survival(C-index:0.6899).CONCLUSION TERT promoter mutation predicts poor prognosis in HBV-related HCC and serves as a biomarker for risk stratification.Optimized dPCR outperforms Sanger sequencing,and nomograms with TERT status guide precision therapy.
基金funded by the National Natural Science Foundation of China(32372585)the Natural Science Foundation of Jiangsu Province,China(BK20231471)the National Training Program of Innovation and Entrepreneurship for Undergraduates,China(202210307013Z)。
文摘The use of RNA interference(RNAi)technology to control pests is explored by researchers globally.Even though RNA is a new class of pest control compound unlike conventional chemical pesticides,the evolution of pest resistance needs to be considered.Here,we first investigate RNAi-based biopesticide resistance of Fusarium asiaticum,which is responsible for devastating diseases of plants,for example,Fusarium head blight.Five resistant strains were isolated from 500 strains that treated with UV-mutagenesis.The mutation common to all of the five resistant mutants occurred in the gene encoding Dicer2(point mutations at codon 1005 and 1007),which were under strong purifying selection pressure.To confirm whether the mutations in Dicer2 confer resistance to RNAi,we exchanged the Dicer2 locus between the sensitive strain and the resistant strain by homologous double exchange.The transformed mutants,Dicer2^(R1005D)and Dicer2^(E1007H),exhibited resistance to dsRNA in vitro.Further study showed that mutations of R1005D and E1007H affected the intramolecular interactions of Dicer2,resulting in the dysfunction of RNase III domain of Dicer2.The amount of sRNAs produced by Dicer2^(R1005D)and Dicer2^(E1007H)was extremely reduced along with variation of sRNA length.Together,these findings revealed a new potential mechanism of RNAi resistance and provided insight into RNAi-related biopesticide deployment for fungal control.
文摘Objective:To investigate the clinical and molecular genetic characteristics of Chinese adolescents with maturity-onset diabetes of the young type 2(MODY 2)and the safety and efficacy of recombinant human growth hormone(r-hGH).Methods:The clinical features and laboratory data of a family with MODY 2 combined with partial growth hormone deficiency(pGHD),diagnosed at the Fourth Clinical Medical College of Xinjiang Medical University,were analyzed.DNA was extracted from peripheral blood using the column method,and Sanger sequencing was conducted to analyze the glucokinase(GCK),hepatocyte nuclear factor 1α(HNF1α),and hepatocyte nuclear factor 4α(HNF4α)in the proband and relevant family members.Results:A heterozygous mutation in GCK(Reference sequence:NM_000162,location:Exon 10)c.1340G>A(p.R447Q)was detected in three family members(the proband,the proband’s younger brother,and their mother).The proband also had pGHD.Conclusion:GCK mutations causing MODY 2 exist in the Chinese population,and the combined treatment with r-hGH is safe and effective.
基金supported by the Jilin Provincial Department of Education Science and Technology Research Project(JJKH20231141K)Natural Science Foundation of Jilin Province of China(20230101154JC)Young Elite Scientists Sponsorship Program by CAST(2022QNRC001)。
文摘Chronic pancreatitis(CP)is a progressive and irreversible fibroinflammatory disease that markedly increases susceptibility to pancreatic cancer and remains without effective targeted therapies.Among the genetic contributors to CP,the carboxypeptidase A1 p.Ser282Pro(CPA1^(S282P))variant has been proposed to promote disease through misfolding-induced endoplasmic reticulum stress(ERS),although the broader pathogenic landscape remains incompletely defined.This study generated a rabbit model mimicking the human CPA1S282P mutation using the SpRY-ABE-8.17 system.Homozygous CPA1^(S282P)rabbits exhibited characteristic human CP phenotypes following alcohol induction,including visceral pain,elevated serum lipase and amylase,inflammatory cell infiltration,and extensive pancreatic fibrosis.Biochemical analyses confirmed that the p.S282P mutation induced CPA1 misfolding and elevated the expression of ERS markers GRP78 and CHOP in both transfected HEK293T cells and homozygous mutant rabbits.Notably,the CPA1^(S282P)mutation markedly disrupted intra-pancreatic lipid homeostasis,contributing to the development of CP in mutant rabbits.This study successfully established the first rabbit model of CP that accurately recapitulates CP caused by a defined human point mutation.Additionally,this study provides insights into a previously unrecognized link between CPA1 and intra-pancreatic lipid metabolism,offering a foundation for identifying novel therapeutic targets for human CP.
基金supported by the Major Program of National Agricultural Science and Technology of China(NK20220607)the Sichuan Science and Technology Program,China(2023YFH0041)。
文摘Starch biosynthesis is a complex process that relies on the coordinated action of multiple enzymes.Resistant starch is not digested in the small intestine,thus preventing a rapid rise in the glycemic index.Starch synthase 2a(SS2a)is a key enzyme in amylopectin biosynthesis that has significant effects on starch structure and properties.In this study,we identified an ss2a null mutant(M3-1413)with a single base mutation from an ethyl methane sulfonate(EMS)-mutagenized population of barley.The mutation was located at the 3'end of the first intron of the RNA splicing receptor(AG)site,and resulted in abnormal RNA splicing and two abnormal transcripts of ss2a,which caused the inactivation of the SS2a gene.The starch structure and properties were significantly altered in the mutant,with M3-1413 containing lower total starch and higher amylose and resistant starch levels.This study sheds light on the effect of barley ss2a null mutations on starch properties and will help to guide new applications of barley starch in the development of nutritious food products.
基金supported by the National Key Research and Development Program of China(Grant No.2022YFD1201600)Earmarked Fund for China Agriculture Research System(Grant No.CARS-26)+1 种基金Chongqing Natural Science Foundation Project(Grant No.CSTB2023NSCQ-MSX1085)Cultivar Improvement of Nanfeng Orange.
文摘The CRISPR/Cas9 system has shown great promise in engineering targeted mutations in a genome.The efficiency of Cas9-mediated genome editing is temperature sensitive.A high-temperature regime can increase the mutation efficiency induced by the CRISPR/Cas9 system in many plant species.However,a heat stress treatment has not been applied during the tissue culture process in citrus.To develop an efficient heat stress regime to improve the efficiency of CRISPR/Cas9-mediated targeted mutagenesis,three and five cycles of heat stress treatments were used during callus induction in citrus.The results showed that the heat stress treatment with three cycles of 24 h at 37℃,followed by 24 h at 26℃,increased the mutation efficiency by 11.6%compared with no heat stress treatment,and that five cycles of heat stress treatment were optimal,from which 50%mutants had a 100%mutation rate.The mutation profiles of Cas9 at 28℃ for 10 d and 37℃ for three or five cycles were similar,indicating that heat stress treatment did not affect the non-homologous end joining repair pathway.No detectable off-target mutation was detected in the potential off-target sites with four nucleotide mismatches compared with the designed on-target site.This study demonstrated that five cycles of heat stress treatment during callus induction could efficiently increase the mutation efficiency mediated by the CRISPR/Cas9 system without observable negative effects,and provided an efficient Cas9-mediated citrus genome editing system to produce mutants with a high mutation rate.
文摘BACKGROUND Familial adenomatous polyposis(FAP)is an autosomal dominant syndrome that results from a germline mutation in the adenomatous polyposis coli gene.It is characterized by the early development of hundreds of adenomas in the colon during the second decade of life.If prophylactic colectomy is not performed,most patients eventually develop colorectal cancer(CRC).CASE SUMMARY We present the mutational profile of a case of FAP that progressed to CRC.A 45-year-old Saudi man presented with intestinal obstruction and underwent a total colectomy.The colon showed hundreds of polyps and two infiltrative ulcerative lesions,which proved to be adenocarcinoma according to histopathology.We performed next-generation sequencing and found mutations in the TP53,NRAS,EGFR PDGFR,MET,KIT,ERBB2,and GUSP genes.CONCLUSION To the best of our knowledge,this case report is the first to sheds the light on the mutation profile of FAP that progressed to CRC in Saudi Arabia.
基金Supported by Clinical Research Center for Precision Medicine of Abdominal Tumor of Fujian Province.
文摘BACKGROUND Pancreatic cancer(PC)is a highly malignant tumor that is resistant to chemotherapy,radiotherapy and immunotherapy.Combination chemotherapy regimens are the standard first-line regimens for metastatic disease,with a median survival<12 months.Although recurrent genomic alterations such as the BRAF V600E mutation have been reported in PC,evidence supporting the clinical effectiveness of molecularly guided targeted therapies is limited.CASE SUMMARY We report a case of a 33-year-old male who was referred to our department with weight loss of 5 kg in 2 months,anorexia and abdominal pain.Imaging showed extensive lesions involving the pancreas,liver,bones,muscles and lymph nodes accompanied by elevated carbohydrate antigen 19-9(CA19-9)and carcinoembryonic antigen(CEA).Biopsy yielded a diagnosis of PC.Treatment with gemcitabine and nab-paclitaxel was initiated,but the disease progressed in<2 months even though the patient’s general condition improved.Molecular testing revealed the presence of BRAF mutation.Dabrafenib/trametinib combination therapy was introduced,and the patient was treated for 2 months with a decrease in CA19-9 and CEA levels,but he died after 2 months of treatment.CONCLUSION BRAF alterations are infrequent in PC.This case highlights the significance of molecular profiling in patients with PC,especially in patients with a high tumor burden.
