A novel mutation of vascular endothelial growth factor receptor gene (VEGFR-3), was identified in a four-generation Chinese family with hereditary lymphedema type I (HL-I). Genetic linkage analysis was performed o...A novel mutation of vascular endothelial growth factor receptor gene (VEGFR-3), was identified in a four-generation Chinese family with hereditary lymphedema type I (HL-I). Genetic linkage analysis was performed on the known genetic locus for HL-I with a panel of polymorphic markers, and then mutations were screened out by direct sequencing. By genotyping, the family showed the linkage to HL-I locus on 5q35.3. Mutation screening analysis of the exons encoding the intracellular kinase domains of VEGFR-3, revealed a novel missense mutation D1055V. This mutation cosegregated with the disease phenotype in the family and was not found in 100 normal controls. This finding has expanded the spectrum of the VEGFR-3 gene mutations causing HL-I, and will be useful for further genetic consultation and genetic diagnosis.展开更多
●AIM:To investigate the molecular diagnosis of a threegeneration Chinese family affected with aniridia,and further to identify clinically a PAX6 missense mutation in members with atypical aniridia.●METHODS:Eleven fa...●AIM:To investigate the molecular diagnosis of a threegeneration Chinese family affected with aniridia,and further to identify clinically a PAX6 missense mutation in members with atypical aniridia.●METHODS:Eleven family members with and without atypical aniridia were recruited.All family members underwent comprehensive ophthalmic examinations.A combination of whole exome sequencing(WES)and direct Sanger sequencing were performed to uncover the causative mutation.●RESULTS:Among the 11 family members,8 were clinically diagnosed with congenital aniridia(atypical aniridia phenotype).A rare heterozygous mutation c.622C>T(p.Arg208Trp)in exon 8 of PAX6 was identified in all affected family members but not in the unaffected members or in healthy control subjects.●CONCLUSION:A rare missense mutation in the PAX6 gene is found in members of a three-generation Chinese family with congenital atypical aniridia.This result contributes to an increase in the phenotypic spectrum caused by PAX6 missense heterozygous variants and provides useful information for the clinical diagnosis of atypical aniridia,which may also contribute to genetic counselling and family planning.展开更多
AIM: To investigate the germline mutations of MSH6 gene in probands of Chinese hereditary non-polyposis colorectal cancer (HNPCC) families fulfilling different clinical criteria. METHODS: Germline mutations of MSH6 ge...AIM: To investigate the germline mutations of MSH6 gene in probands of Chinese hereditary non-polyposis colorectal cancer (HNPCC) families fulfilling different clinical criteria. METHODS: Germline mutations of MSH6 gene were detected by PCR-based DNA sequencing in 39 unrelated HNPCC probands fulfilling different clinical criteria in which MSH2 and MLH1 mutations were excluded. To further investigate the pathological effects of detected missense mutations, we analyzed the above related MSH6 exons using PCR-based sequencing in 137 healthy persons with no family history. The clinicopathological features were collected from the Archive Library of Cancer Hospital, Fudan University and analyzed. RESULTS: Four germline missense mutations distributed in the 4th, 6th and 9th exons were observed. Of them, three were not found in international HNPCC databases and did not occur in 137 healthy controls, indicating that they were novel missense mutations. The remaining mutation which is consistent with the case H14 at c.3488A>T of exon 6 of MSH6 gene was also found in the controls, the rate was approximately 3.65% (5/137) and the type of mutation was not found in the international HNPCC mutational and SNP databases, suggesting that this missense mutation was a new SNP unreported up to date. CONCLUSION: Three novel missense mutations and a new SNP observed in the probands of Chinese HNPCC families, may play an important role in the development of HNPCC.展开更多
AIMTo identify the genetic defects in a Chinese family with achromatopsia.METHODSA 2.5-year-old boy, who displayed nystagmus, photophobia, and hyperopia since early infancy, was clinically evaluated. To further confir...AIMTo identify the genetic defects in a Chinese family with achromatopsia.METHODSA 2.5-year-old boy, who displayed nystagmus, photophobia, and hyperopia since early infancy, was clinically evaluated. To further confirm and localize the causative mutations in this family, targeted region capture and next-generation sequencing of candidate genes, such as CNGA3, CNGB3, GNAT2, PDE6C, and PDE6H were performed using a custom-made capture array.RESULTSSlit-lamp examination showed no specific findings in the anterior segments. The optic discs and maculae were normal on fundoscopy. The unaffected family members reported no ocular complaints. Clinical signs and symptoms were consistent with a clinical impression of autosomal recessive achromatopsia. The results of sequence analysis revealed two novel missense mutations in CNGA3, c.633T>A (p.D211E) and c.1006G>T (p.V336F), with an autosomal recessive mode of inheritance.CONCLUSIONGenetic analysis of a Chinese family confirmed the clinical diagnosis of achromatopsia. Two novel mutations were identified in CNGA3, which extended the mutation spectrum of this disorder.展开更多
Tooth development is a complex process that involves precise and time-dependent orchestration of multiple genetic, molecular,and cellular interactions. Ameloblastin(AMBN, also named "amelin" or "sheathl...Tooth development is a complex process that involves precise and time-dependent orchestration of multiple genetic, molecular,and cellular interactions. Ameloblastin(AMBN, also named "amelin" or "sheathlin") is the second most abundant enamel matrix protein known to have a key role in amelogenesis. Amelogenesis imperfecta(AI [MIM: 104500]) refers to a genetically and phenotypically heterogeneous group of conditions characterized by inherited developmental enamel defects. The hereditary dentin disorders comprise a variety of autosomal-dominant genetic symptoms characterized by abnormal dentin structure affecting either the primary or both the primary and secondary teeth. The vital role of Ambn in amelogenesis has been confirmed experimentally using mouse models. Only two cases have been reported of mutations of AMBN associated with non-syndromic human AI. However, no AMBN missense mutations have been reported to be associated with both human AI and dentin disorders.We recruited one kindred with autosomal-dominant amelogenesis imperfecta(ADAI) and dentinogenesis imperfecta/dysplasia characterized by generalized severe enamel and dentin defects. Whole exome sequencing of the proband identified a novel heterozygous C-T point mutation at nucleotide position 1069 of the AMBN gene, causing a Pro to Ser mutation at the conserved amino acid position 357 of the protein. Exfoliated third molar teeth from the affected family members were found to have enamel and dentin of lower mineral density than control teeth, with thinner and easily fractured enamel, short and thick roots, and pulp obliteration. This study demonstrates, for the first time, that an AMBN missense mutation causes non-syndromic human AI and dentin disorders.展开更多
Multiple morphological abnormalities of the sperm flagella(MMAF)are characterized by bent,irregular,short,coiled,and absent flagella.MMAF is caused by a variety of genes,some of which have been identified.However,the ...Multiple morphological abnormalities of the sperm flagella(MMAF)are characterized by bent,irregular,short,coiled,and absent flagella.MMAF is caused by a variety of genes,some of which have been identified.However,the underlying genetic factors responsible for the majority of MMAF cases are still largely unknown.The glutamine-rich 2(QRICH2)gene plays an essential role in the development of sperm flagella by regulating the expression of essential sperm flagellar biogenesis-associated proteins,and genetic variants of QRICH2 have been identified as the primary cause of MMAF in humans and mice.Here,we recruited a Pakistani consanguineous family to identify the genetic variant causing infertility in patients with MMAF.Whole-exome sequencing and Sanger sequencing were conducted to identify potentially pathogenic variants causing MMAF in infertile patients.Hematoxylin and eosin(HE)staining was performed to analyze sperm morphology.Quantitative polymerase chain reaction,western blot,and immunofluorescence staining analyses were conducted to observe the expression of QRICH2 in spermatozoa.A novel homozygous missense variant(c.4618C>T)in QRICH2 was identified in the affected patients.Morphological analysis of spermatozoa revealed the MMAF phenotype in infertile patients.qPCR revealed a significant reduction in the level of sperm QRICH2 mRNA,and immunofluorescence staining revealed a lack of sperm QRICH2 expression.Additionally,patients harboring a homozygous QRICH2 mutation presented reduced expression of outer dense fiber 2(ODF2)in sperm,whereas sperm expression of A-kinase anchor protein 4(AKAP4)was normal.These findings expand our understanding of the genetic causes of MMAF-associated male infertility and emphasize the importance of genetic counseling.展开更多
Male infertility is a worldwide health issue,affecting 8%–12%of the global population.Oligoasthenoteratozoospermia(OAT)represents a severe type of male infertility,characterized by reduced sperm count and motility an...Male infertility is a worldwide health issue,affecting 8%–12%of the global population.Oligoasthenoteratozoospermia(OAT)represents a severe type of male infertility,characterized by reduced sperm count and motility and an increased frequency of sperm with aberrant morphology.Using whole-exome sequencing,this study identified a novel missense mutation(c.848C>A,p.A283E)in the coiled-coil domain-containing 34 gene(CCDC34)in a consanguineous Pakistani family.This rare mutation was predicted to be deleterious and to affect the protein stability.Hematoxylin and eosin staining of spermatozoa from the patient with OAT revealed multiple morphological abnormalities of the flagella and transmission electron microscopy indicated axonemal ultrastructural defects with a lack of outer dynein arms.These findings indicated that CCDC34 plays a role in maintaining the axonemal ultrastructure and the assembly or stability of the outer dynein arms,thus expanding the phenotypic spectrum of CCDC34 missense mutations.展开更多
PIK3R5 is the regulatory subunit of Phosphoinositide 3-kinase γ (PI3Kγ) that is responsible for phosphory-lating membrane lipids to activate the AKT pathway. PIK3R5 binds Gβγ and facilitates the interaction with p...PIK3R5 is the regulatory subunit of Phosphoinositide 3-kinase γ (PI3Kγ) that is responsible for phosphory-lating membrane lipids to activate the AKT pathway. PIK3R5 binds Gβγ and facilitates the interaction with p110γ catalytic subunit (PIK3CG) during PI3Kγ activation. The identification of PIK3R5 P629S mutation in AOA2 patients indicated a potential defect in the AKT pathway resulting from impaired PIK3R5 interaction with Gβγ and PIK3CG, defective AKT pathway can result in cerebellar cell death causing neurological symptoms. Our in silico macromolecular docking of the wild type and mutant PIK3R5 protein models with ligand revealed an energy requirement to maintain the mutant complexes compared to no energy required to maintain the wild type complexes, in addition, the mutant structures were loose compared to rigid wild type structures, such structural changes may impair the molecular function of the PIK3R5 and hence affect the AKT pathway.展开更多
·AIM: To identify the pathogenic mutations in a Chinese pedigree affected with Usher syndrome type II(USH2).· METHODS: The ophthalmic examinations and audiometric tests were performed to ascertain the phenot...·AIM: To identify the pathogenic mutations in a Chinese pedigree affected with Usher syndrome type II(USH2).· METHODS: The ophthalmic examinations and audiometric tests were performed to ascertain the phenotype of the family. To detect the genetic defect,exons of 103 known RDs-associated genes including 12 Usher syndrome(USH) genes of the proband were captured and sequencing analysis was performed to exclude known genetic defects and find potential pathogenic mutations. Subsequently, candidate mutations were validated in his pedigree and 100 normal controls using polymerase chain reaction(PCR) and Sanger sequencing.·RESULTS: The patient in the family occurred hearing loss(HL) and retinitis pigmentosa(RP) without vestibular dysfunction, which were consistent with standards of classification for USH2. He carried the compound heterozygous mutations, c.721 C 】T and c.1969 C 】T, in the MYO7 A gene and the unaffected members carried only one of the two mutations. The mutations were not present in the 100 normal controls.· CONCLUSION: We suggested that the compound heterozygous mutations of the MYO7 A could lead to USH2, which had revealed distinguished clinical phenotypes associated with MYO7 A and expanded the spectrum of clinical phenotypes of the MYO7 A mutations.展开更多
Steroid 5β-reductase [aldo-keto reductase family 1 member D1(AKR1D1)] is essential for bile acid biosynthesis. Bile acid deficiency caused by genetic defects in AKR1D1 leads to life-threatening neonatal hepatitis and...Steroid 5β-reductase [aldo-keto reductase family 1 member D1(AKR1D1)] is essential for bile acid biosynthesis. Bile acid deficiency caused by genetic defects in AKR1D1 leads to life-threatening neonatal hepatitis and cholestasis. There is still limited experience regarding the treatment of this disease. We describe an infant who presented with hyperbilirubinemia and coagulopathy but normal bile acid and γ-glutamyltransferase. Gene analysis was performed using genomic DNA from peripheral lymphocytes from the patient, his parents, and his elder brother. The patient was compound heterozygous for c.919C>T in exon 8 and exhibited a loss of heterozygosity of the AKR1D1 gene, which led to an amino acid substitution of arginine by cysteine at amino acid position 307(p.R307C). Based on these mutations, the patient was confirmed to have primary 5β-reductase deficiency. Ursodeoxycholic acid(UDCA) treatment did not have any effect on the patient. However, when we changed to chenodeoxycholic acid(CDCA) treatment, his symptoms and laboratory tests gradually improved. It is therefore crucial to supplement with an adequate dose of CDCA early to improve clinical symptoms and to normalize laboratory tests.展开更多
Race, family history and age are the unequivocally accepted risk factors for prostate cancer (PCa). Androgen receptor (AR)-dependent signaling is an important element in prostate carcinogenesis and its progression...Race, family history and age are the unequivocally accepted risk factors for prostate cancer (PCa). Androgen receptor (AR)-dependent signaling is an important element in prostate carcinogenesis and its progression to metastatic disease. We examined the possibility of genomic changes in the AR in association with familial PCa in African Americans who have a higher incidence and mortality rate and a clinically more aggressive disease presentation than Caucasians. Genomic DNAs of 60 patients from 30 high-risk African American and Caucasian families participating in the Louisiana State University Health Sciences Center genetic linkage study of PCa were studied. Exon-specific polymerase-chain reaction, bi-directional automated sequencing and restriction enzyme genotyping were used to analyze for mutations in the coding region of the AR gene. We identified a germline AR (A1675T) (T559S) substitution mutation in the DNA-binding domain in three PCa-affected members of an African- American family with a history of early-onset disease. The present study describes the first AR germline mutation in an African-American family with a history of familial PCa. The AR (T559S) mutation may contribute to the disease by altering AR DNA-binding affinity and/or its response to androgens, non-androgenic steroids or anti-androgens. Additional studies will be required to define the frequency and contribution of the AR (A 1675T) allele to early-onset and/or familial PCa in African Americans.展开更多
Non-syndromic low-frequency sensorineural hearing loss (LFSNHL) is an unusual type of hearing loss in which frequencies ≤2000 Hz predominantly are affected. To date, different mutations in two genes, DIAPHI and WFS...Non-syndromic low-frequency sensorineural hearing loss (LFSNHL) is an unusual type of hearing loss in which frequencies ≤2000 Hz predominantly are affected. To date, different mutations in two genes, DIAPHI and WFSI, have been found to be associated with LFSNHL. Here, we report a five-generation Chinese family with postlingual and progressive LFSNHL. We mapped the disease locus to a 2.5 Mb region on chromosome 4p16 between markers SNP_A-2167174 and D4S431, overlapping with the DFNA6/14/38 locus. Sequencing of candidate gene revealed a heterozygous c.2086C〉T substitution in exon 8 of WFS1, leading to p.H696Y substitution at the C-terminus of Wolframin (WFS 1). In addition, we performed mutational screening of WFS1 in 37 sporadic patients, 7--50 years of age, with LFSNHL. We detected a heterozygous c.2108G〉A substitution in exon 8 of WFSI, leading to p.R703H substitution in a patient. The H696 and R703 in WFS1 are highly conserved across species, including human, orangutan, rat, mouse, and frog (Xenopus), Sequence analysis demonstrated the absence of c.2086C〉T or c.210gG〉A substitutions in the WFS1 genes among 200 unrelated control subjects of Chinese background, supporting the hypothesis that they represent causative mutations, and not rare polymorphisms. Our data provide additional molecular and clinical information for establishing a better genotype-phenotype correlation for LFSNHL.展开更多
Oculocutaneous albinism (OCA)is an autosomal recessive pigmentation abnormality,characterized by variable hair,skin,and ocular hypopigmentation.OCA1 is the most frequent subtype of OCA,caused by mutations in the tyros...Oculocutaneous albinism (OCA)is an autosomal recessive pigmentation abnormality,characterized by variable hair,skin,and ocular hypopigmentation.OCA1 is the most frequent subtype of OCA,caused by mutations in the tyrosinase gene (TYR). In this study,we investigated the genetic mutation of a Chinese family with a female OCA patient who came for genetic counseling before pregnancy.Complete physical examination was performed,and DNA from blood samples was collected from the family members.Mutations of TYR,OCA2,and SLC45A2 genes were examined in the proband, and verified in her parents by Sanger sequencing.Large deletion or duplication of TYR and OCA2 genes was detected by multiplex ligation-dependent probe amplification (MLPA).A homozygous TYR c.307T>C (p.Cys103Arg)missense mutation was identified in the proband,and both parents were heterozygous carriers.No large deletion or duplication was found in the proband.This mutation was absent in 1000G,ExAC,or HGMD database,and multiple lines of in silico tools supported a deleterious effect.These results suggest that TYR c.307T>C mutation might be responsible for OCA1,and our study further expands the mutation spectrum of OCA1 in the Chinese population.展开更多
Objective :To study the gene mutations of homeobox transcription factor (CSX/NKX2.5) associated with a Chinese family with secundum atrial septal defect (ASD). Methods :Polymerase chain reaction and DNA sequenci...Objective :To study the gene mutations of homeobox transcription factor (CSX/NKX2.5) associated with a Chinese family with secundum atrial septal defect (ASD). Methods :Polymerase chain reaction and DNA sequencing were used to check all the members in the family with ASD, and single strand conformation polymorphism analysis (SSCP) was used to check 126 normal control people for detecting the mutations of CSX/NKX2.5 gene. Results: Three mutations, G270A(Glu32Lys ), G378A (Glu68Lys)andG390A (Glu72Lys)were identified in CSX/NKX2.5 gene of ASD patients. However, the other members in the family with ASD and the control did not have such gene mutations. Conclusion:These mutations of CSX/NKX2.5 gene, which were identified in a Chinese family, may be one of the secundum ASD etiologic causes .展开更多
The population of early-onset Alzheimer's disease(EOAD)accounts for 1%-2%of the total population of Alzheimer's disease,and genetic mutations are more common in EOAD.The first symptom of the patient in the pre...The population of early-onset Alzheimer's disease(EOAD)accounts for 1%-2%of the total population of Alzheimer's disease,and genetic mutations are more common in EOAD.The first symptom of the patient in the present case report was the decline in memories of recent events,and the disease progressed rapidly in the following 2 years.Genetic testing has revealed the presence of genetic mutations(c.A479G,p.N160S)of ACE,which causes the 160th codon of the ACE protein to change from aspartic acid to serine,and at the same time genotype of apolipoprotein E(APOE)is ε3/ε4.We think that this patient carries the mutation type of the sensitive gene ACE and the risk gene APOE of Alzheimer's disease,and this is the reason why the disease progressed rapidly.Moreover,we discussed ACE genetic mutation's meaning in EOAD progression.展开更多
BACKGROUND Autosomal dominant tubulointerstitial kidney disease(ADTKD)is a progressive chronic disease that is inherited in an autosomal dominant fashion.Symptoms include hyperuricemia,gout,interstitial nephritis,rena...BACKGROUND Autosomal dominant tubulointerstitial kidney disease(ADTKD)is a progressive chronic disease that is inherited in an autosomal dominant fashion.Symptoms include hyperuricemia,gout,interstitial nephritis,renal cysts,and progressive renal damage that can lead to end-stage renal disease.Mutations in the uromodulin gene(UMOD)characterize the ADTKD-UMOD clinical subtype of this disease.To date,>100 UMOD mutations have been identified.Early diagnosis of ADTKD-UMOD is important to treat the disease,slow down disease progression,and facilitate the identification of potentially affected family members.CASE SUMMARY We report a 40-year-old man harboring a novel heterozygous missense mutation in UMOD(c.554G>T;p.Arg185Leu).The patient had hyperuricemia,gout,and chronic kidney disease.The same mutation was detected in his daughter,aunt and cousin.CONCLUSION A single nucleotide substitution in exon 3 of UMOD was responsible for the heterozygous missense mutation(c.554G>T,p.Arg185Leu).展开更多
Congenital bilateral absence of the vas deferens(CBAVD)is observed in 1%–2%of males presenting with infertility and is clearly associated with cystic fibrosis transmembrane conductance regulator(CFTR)mutations.CFTR i...Congenital bilateral absence of the vas deferens(CBAVD)is observed in 1%–2%of males presenting with infertility and is clearly associated with cystic fibrosis transmembrane conductance regulator(CFTR)mutations.CFTR is one of the most well-known genes related to male fertility.The frequency of CFTR mutations or impaired CFTR expression is increased in men with nonobstructive azoospermia(NOA).CFTR mutations are highly polymorphic and have established ethnic specificity.Compared with F508Del in Caucasians,the p.G970D mutation is reported to be the most frequent CFTR mutation in Chinese patients with cystic fibrosis.However,whether p.G970D participates in male infertility remains unknown.Herein,a loss-of-function CFTR p.G970D missense mutation was identified in a patient with CBAVD and NOA.Subsequent retrospective analysis of 122 Chinese patients with CBAVD showed that the mutation is a common pathogenic mutation(4.1%,5/122),excluding polymorphic sites.Furthermore,we generated model cell lines derived from mouse testes harboring the homozygous Cftr p.G965D mutation equivalent to the CFTR variant in patients.The Cftr p.G965D mutation may be lethal in spermatogonial stem cells and spermatogonia and affect the proliferation of spermatocytes and Sertoli cells.In spermatocyte GC-2(spd)ts(GC2)Cftr p.G965D cells,RNA splicing variants were detected and CFTR expression decreased,which may contribute to the phenotypes associated with impaired spermatogenesis.Thus,this study indicated that the CFTR p.G970D missense mutation might be a pathogenic mutation for CBAVD in Chinese males and associated with impaired spermatogenesis by affecting the proliferation of germ cells.展开更多
We have analyzed the exons 13, 16, 21 and 23 of cardiac myosin heavy chain gene in 32 Chinese patients with hypertrophic cardiomyopathy by using PCR-single strand conformation polymorphism (PCR-SSCP) procedure. The re...We have analyzed the exons 13, 16, 21 and 23 of cardiac myosin heavy chain gene in 32 Chinese patients with hypertrophic cardiomyopathy by using PCR-single strand conformation polymorphism (PCR-SSCP) procedure. The result showed an altered SSCP of the exon 13 in one patient. Sequencing analysis revealed that the patient had a G to T transversion in the codon 383, resulting in the substitution of Lys by Asn. Beacause the missense mutation was found at the residue highly conserved through species evolution, this mutation is likely, to be the cause of hypertrophic cardiomyopathy in this patient. This is the first report of a mutant cardiac β-MHC gene in the Chinese population. Also, it is a novel missense mutation of the cardiac β-MHC gene.展开更多
PiT2 is an inorganic phosphate(Pi)transporter whose mutations are linked to primary familial brain calcification(PFBC).PiT2 mainly consists of two ProDom(PD)domains and a large intracellular loop region(loop7).The PD ...PiT2 is an inorganic phosphate(Pi)transporter whose mutations are linked to primary familial brain calcification(PFBC).PiT2 mainly consists of two ProDom(PD)domains and a large intracellular loop region(loop7).The PD domains are crucial for the Pi transport,but the role of PiT2-loop7 remains unclear.In PFBC patients,mutations in PiT2-loop7 are mainly nonsense or frameshift mutations that probably cause PFBC due to C-PD1131 deletion.To date,six missense mutations have been identified in PiT2-loop7;however,the mechanisms by which these mutations cause PFBC are poorly understood.Here,we found that the p.T390A and p.S434W mutations in PiT2-loop7 decreased the Pi transport activity and cell surface levels of PiT2.Furthermore,we showed that these two mutations attenuated its membrane localization by affecting adenosine monophosphate-activated protein kinase(AMPK)-or protein kinase B(AKT)-mediated PiT2 phosphorylation.In contrast,the p.S121C and p.S601W mutations in the PD domains did not affect PiT2 phosphorylation but rather impaired its substrate-binding abilities.These results suggested that missense mutations in PiT2-loop7 can cause Pi dyshomeostasis by affecting the phosphorylation-regulated cell-surface localization of PiT2.This study helps understand the pathogenesis of PFBC caused by PiT2-loop7 missense mutations and indicates that increasing the phosphorylation levels of PiT2-loop7 could be a promising strategy for developing PFBC therapies.展开更多
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
文摘A novel mutation of vascular endothelial growth factor receptor gene (VEGFR-3), was identified in a four-generation Chinese family with hereditary lymphedema type I (HL-I). Genetic linkage analysis was performed on the known genetic locus for HL-I with a panel of polymorphic markers, and then mutations were screened out by direct sequencing. By genotyping, the family showed the linkage to HL-I locus on 5q35.3. Mutation screening analysis of the exons encoding the intracellular kinase domains of VEGFR-3, revealed a novel missense mutation D1055V. This mutation cosegregated with the disease phenotype in the family and was not found in 100 normal controls. This finding has expanded the spectrum of the VEGFR-3 gene mutations causing HL-I, and will be useful for further genetic consultation and genetic diagnosis.
文摘●AIM:To investigate the molecular diagnosis of a threegeneration Chinese family affected with aniridia,and further to identify clinically a PAX6 missense mutation in members with atypical aniridia.●METHODS:Eleven family members with and without atypical aniridia were recruited.All family members underwent comprehensive ophthalmic examinations.A combination of whole exome sequencing(WES)and direct Sanger sequencing were performed to uncover the causative mutation.●RESULTS:Among the 11 family members,8 were clinically diagnosed with congenital aniridia(atypical aniridia phenotype).A rare heterozygous mutation c.622C>T(p.Arg208Trp)in exon 8 of PAX6 was identified in all affected family members but not in the unaffected members or in healthy control subjects.●CONCLUSION:A rare missense mutation in the PAX6 gene is found in members of a three-generation Chinese family with congenital atypical aniridia.This result contributes to an increase in the phenotypic spectrum caused by PAX6 missense heterozygous variants and provides useful information for the clinical diagnosis of atypical aniridia,which may also contribute to genetic counselling and family planning.
基金Supported by Shanghai Medical Development Fund for Major Projects, No. 05Ⅲ004 and Shanghai Pu Jiang Projects for Talented-Men, 06PJ14019
文摘AIM: To investigate the germline mutations of MSH6 gene in probands of Chinese hereditary non-polyposis colorectal cancer (HNPCC) families fulfilling different clinical criteria. METHODS: Germline mutations of MSH6 gene were detected by PCR-based DNA sequencing in 39 unrelated HNPCC probands fulfilling different clinical criteria in which MSH2 and MLH1 mutations were excluded. To further investigate the pathological effects of detected missense mutations, we analyzed the above related MSH6 exons using PCR-based sequencing in 137 healthy persons with no family history. The clinicopathological features were collected from the Archive Library of Cancer Hospital, Fudan University and analyzed. RESULTS: Four germline missense mutations distributed in the 4th, 6th and 9th exons were observed. Of them, three were not found in international HNPCC databases and did not occur in 137 healthy controls, indicating that they were novel missense mutations. The remaining mutation which is consistent with the case H14 at c.3488A>T of exon 6 of MSH6 gene was also found in the controls, the rate was approximately 3.65% (5/137) and the type of mutation was not found in the international HNPCC mutational and SNP databases, suggesting that this missense mutation was a new SNP unreported up to date. CONCLUSION: Three novel missense mutations and a new SNP observed in the probands of Chinese HNPCC families, may play an important role in the development of HNPCC.
基金Supported by the National Natural Science Foundation of China(No.81371005No.31100991)
文摘AIMTo identify the genetic defects in a Chinese family with achromatopsia.METHODSA 2.5-year-old boy, who displayed nystagmus, photophobia, and hyperopia since early infancy, was clinically evaluated. To further confirm and localize the causative mutations in this family, targeted region capture and next-generation sequencing of candidate genes, such as CNGA3, CNGB3, GNAT2, PDE6C, and PDE6H were performed using a custom-made capture array.RESULTSSlit-lamp examination showed no specific findings in the anterior segments. The optic discs and maculae were normal on fundoscopy. The unaffected family members reported no ocular complaints. Clinical signs and symptoms were consistent with a clinical impression of autosomal recessive achromatopsia. The results of sequence analysis revealed two novel missense mutations in CNGA3, c.633T>A (p.D211E) and c.1006G>T (p.V336F), with an autosomal recessive mode of inheritance.CONCLUSIONGenetic analysis of a Chinese family confirmed the clinical diagnosis of achromatopsia. Two novel mutations were identified in CNGA3, which extended the mutation spectrum of this disorder.
基金partially supported by a grant from the National Natural Science Foundation of China 31371279 (to Fu Xiong)the National Natural Science Foundation of China 81371137 (to Bu-Ling Wu)the Science and Technology Program of Guangzhou 201707010301 (to Fu Xiong)
文摘Tooth development is a complex process that involves precise and time-dependent orchestration of multiple genetic, molecular,and cellular interactions. Ameloblastin(AMBN, also named "amelin" or "sheathlin") is the second most abundant enamel matrix protein known to have a key role in amelogenesis. Amelogenesis imperfecta(AI [MIM: 104500]) refers to a genetically and phenotypically heterogeneous group of conditions characterized by inherited developmental enamel defects. The hereditary dentin disorders comprise a variety of autosomal-dominant genetic symptoms characterized by abnormal dentin structure affecting either the primary or both the primary and secondary teeth. The vital role of Ambn in amelogenesis has been confirmed experimentally using mouse models. Only two cases have been reported of mutations of AMBN associated with non-syndromic human AI. However, no AMBN missense mutations have been reported to be associated with both human AI and dentin disorders.We recruited one kindred with autosomal-dominant amelogenesis imperfecta(ADAI) and dentinogenesis imperfecta/dysplasia characterized by generalized severe enamel and dentin defects. Whole exome sequencing of the proband identified a novel heterozygous C-T point mutation at nucleotide position 1069 of the AMBN gene, causing a Pro to Ser mutation at the conserved amino acid position 357 of the protein. Exfoliated third molar teeth from the affected family members were found to have enamel and dentin of lower mineral density than control teeth, with thinner and easily fractured enamel, short and thick roots, and pulp obliteration. This study demonstrates, for the first time, that an AMBN missense mutation causes non-syndromic human AI and dentin disorders.
基金supported by the National Key Research and Development Program of China(2021YFC2700202,2022YFA0806303 and 2022YFC2702601)the Global Select Project of the Institute of Health and Medicine,Hefei Comprehensive National Science Center(DJK-LX-2022010)+1 种基金USTC Research Funds of the Double First-Class Initiative(the Joint Fund for New Medicine of USTC)(YD9100002034)the Fundamental Research Funds for the Central Universities(WK9100000004).
文摘Multiple morphological abnormalities of the sperm flagella(MMAF)are characterized by bent,irregular,short,coiled,and absent flagella.MMAF is caused by a variety of genes,some of which have been identified.However,the underlying genetic factors responsible for the majority of MMAF cases are still largely unknown.The glutamine-rich 2(QRICH2)gene plays an essential role in the development of sperm flagella by regulating the expression of essential sperm flagellar biogenesis-associated proteins,and genetic variants of QRICH2 have been identified as the primary cause of MMAF in humans and mice.Here,we recruited a Pakistani consanguineous family to identify the genetic variant causing infertility in patients with MMAF.Whole-exome sequencing and Sanger sequencing were conducted to identify potentially pathogenic variants causing MMAF in infertile patients.Hematoxylin and eosin(HE)staining was performed to analyze sperm morphology.Quantitative polymerase chain reaction,western blot,and immunofluorescence staining analyses were conducted to observe the expression of QRICH2 in spermatozoa.A novel homozygous missense variant(c.4618C>T)in QRICH2 was identified in the affected patients.Morphological analysis of spermatozoa revealed the MMAF phenotype in infertile patients.qPCR revealed a significant reduction in the level of sperm QRICH2 mRNA,and immunofluorescence staining revealed a lack of sperm QRICH2 expression.Additionally,patients harboring a homozygous QRICH2 mutation presented reduced expression of outer dense fiber 2(ODF2)in sperm,whereas sperm expression of A-kinase anchor protein 4(AKAP4)was normal.These findings expand our understanding of the genetic causes of MMAF-associated male infertility and emphasize the importance of genetic counseling.
基金supported by the National Natural Science Foundation of China(No.82071709,No.32070850,and No.82171601)the National Key Research and Developmental Program of China(2022YFC2702601 and 2022YFA0806303)the Joint Fund for New Medicine of USTC(YD9100002034).
文摘Male infertility is a worldwide health issue,affecting 8%–12%of the global population.Oligoasthenoteratozoospermia(OAT)represents a severe type of male infertility,characterized by reduced sperm count and motility and an increased frequency of sperm with aberrant morphology.Using whole-exome sequencing,this study identified a novel missense mutation(c.848C>A,p.A283E)in the coiled-coil domain-containing 34 gene(CCDC34)in a consanguineous Pakistani family.This rare mutation was predicted to be deleterious and to affect the protein stability.Hematoxylin and eosin staining of spermatozoa from the patient with OAT revealed multiple morphological abnormalities of the flagella and transmission electron microscopy indicated axonemal ultrastructural defects with a lack of outer dynein arms.These findings indicated that CCDC34 plays a role in maintaining the axonemal ultrastructure and the assembly or stability of the outer dynein arms,thus expanding the phenotypic spectrum of CCDC34 missense mutations.
文摘PIK3R5 is the regulatory subunit of Phosphoinositide 3-kinase γ (PI3Kγ) that is responsible for phosphory-lating membrane lipids to activate the AKT pathway. PIK3R5 binds Gβγ and facilitates the interaction with p110γ catalytic subunit (PIK3CG) during PI3Kγ activation. The identification of PIK3R5 P629S mutation in AOA2 patients indicated a potential defect in the AKT pathway resulting from impaired PIK3R5 interaction with Gβγ and PIK3CG, defective AKT pathway can result in cerebellar cell death causing neurological symptoms. Our in silico macromolecular docking of the wild type and mutant PIK3R5 protein models with ligand revealed an energy requirement to maintain the mutant complexes compared to no energy required to maintain the wild type complexes, in addition, the mutant structures were loose compared to rigid wild type structures, such structural changes may impair the molecular function of the PIK3R5 and hence affect the AKT pathway.
基金Supported by the Postdoctoral Science Foundation of China(No.2014M562542)
文摘·AIM: To identify the pathogenic mutations in a Chinese pedigree affected with Usher syndrome type II(USH2).· METHODS: The ophthalmic examinations and audiometric tests were performed to ascertain the phenotype of the family. To detect the genetic defect,exons of 103 known RDs-associated genes including 12 Usher syndrome(USH) genes of the proband were captured and sequencing analysis was performed to exclude known genetic defects and find potential pathogenic mutations. Subsequently, candidate mutations were validated in his pedigree and 100 normal controls using polymerase chain reaction(PCR) and Sanger sequencing.·RESULTS: The patient in the family occurred hearing loss(HL) and retinitis pigmentosa(RP) without vestibular dysfunction, which were consistent with standards of classification for USH2. He carried the compound heterozygous mutations, c.721 C 】T and c.1969 C 】T, in the MYO7 A gene and the unaffected members carried only one of the two mutations. The mutations were not present in the 100 normal controls.· CONCLUSION: We suggested that the compound heterozygous mutations of the MYO7 A could lead to USH2, which had revealed distinguished clinical phenotypes associated with MYO7 A and expanded the spectrum of clinical phenotypes of the MYO7 A mutations.
基金the Guangdong Medical Research Foundation,No.A2018550
文摘Steroid 5β-reductase [aldo-keto reductase family 1 member D1(AKR1D1)] is essential for bile acid biosynthesis. Bile acid deficiency caused by genetic defects in AKR1D1 leads to life-threatening neonatal hepatitis and cholestasis. There is still limited experience regarding the treatment of this disease. We describe an infant who presented with hyperbilirubinemia and coagulopathy but normal bile acid and γ-glutamyltransferase. Gene analysis was performed using genomic DNA from peripheral lymphocytes from the patient, his parents, and his elder brother. The patient was compound heterozygous for c.919C>T in exon 8 and exhibited a loss of heterozygosity of the AKR1D1 gene, which led to an amino acid substitution of arginine by cysteine at amino acid position 307(p.R307C). Based on these mutations, the patient was confirmed to have primary 5β-reductase deficiency. Ursodeoxycholic acid(UDCA) treatment did not have any effect on the patient. However, when we changed to chenodeoxycholic acid(CDCA) treatment, his symptoms and laboratory tests gradually improved. It is therefore crucial to supplement with an adequate dose of CDCA early to improve clinical symptoms and to normalize laboratory tests.
文摘Race, family history and age are the unequivocally accepted risk factors for prostate cancer (PCa). Androgen receptor (AR)-dependent signaling is an important element in prostate carcinogenesis and its progression to metastatic disease. We examined the possibility of genomic changes in the AR in association with familial PCa in African Americans who have a higher incidence and mortality rate and a clinically more aggressive disease presentation than Caucasians. Genomic DNAs of 60 patients from 30 high-risk African American and Caucasian families participating in the Louisiana State University Health Sciences Center genetic linkage study of PCa were studied. Exon-specific polymerase-chain reaction, bi-directional automated sequencing and restriction enzyme genotyping were used to analyze for mutations in the coding region of the AR gene. We identified a germline AR (A1675T) (T559S) substitution mutation in the DNA-binding domain in three PCa-affected members of an African- American family with a history of early-onset disease. The present study describes the first AR germline mutation in an African-American family with a history of familial PCa. The AR (T559S) mutation may contribute to the disease by altering AR DNA-binding affinity and/or its response to androgens, non-androgenic steroids or anti-androgens. Additional studies will be required to define the frequency and contribution of the AR (A 1675T) allele to early-onset and/or familial PCa in African Americans.
基金supported by the National High Technology Research and Development Program of China(863 Program) to Huijun Yuan(No.2007AA02E466)Key Project of National Natural Science Foundation of China to Huijun Yuan (No.81030017)and to Pu Dai(No.30872862)
文摘Non-syndromic low-frequency sensorineural hearing loss (LFSNHL) is an unusual type of hearing loss in which frequencies ≤2000 Hz predominantly are affected. To date, different mutations in two genes, DIAPHI and WFSI, have been found to be associated with LFSNHL. Here, we report a five-generation Chinese family with postlingual and progressive LFSNHL. We mapped the disease locus to a 2.5 Mb region on chromosome 4p16 between markers SNP_A-2167174 and D4S431, overlapping with the DFNA6/14/38 locus. Sequencing of candidate gene revealed a heterozygous c.2086C〉T substitution in exon 8 of WFS1, leading to p.H696Y substitution at the C-terminus of Wolframin (WFS 1). In addition, we performed mutational screening of WFS1 in 37 sporadic patients, 7--50 years of age, with LFSNHL. We detected a heterozygous c.2108G〉A substitution in exon 8 of WFSI, leading to p.R703H substitution in a patient. The H696 and R703 in WFS1 are highly conserved across species, including human, orangutan, rat, mouse, and frog (Xenopus), Sequence analysis demonstrated the absence of c.2086C〉T or c.210gG〉A substitutions in the WFS1 genes among 200 unrelated control subjects of Chinese background, supporting the hypothesis that they represent causative mutations, and not rare polymorphisms. Our data provide additional molecular and clinical information for establishing a better genotype-phenotype correlation for LFSNHL.
基金This project was supported by the National Natural Science Foundation of China (No.81500925).
文摘Oculocutaneous albinism (OCA)is an autosomal recessive pigmentation abnormality,characterized by variable hair,skin,and ocular hypopigmentation.OCA1 is the most frequent subtype of OCA,caused by mutations in the tyrosinase gene (TYR). In this study,we investigated the genetic mutation of a Chinese family with a female OCA patient who came for genetic counseling before pregnancy.Complete physical examination was performed,and DNA from blood samples was collected from the family members.Mutations of TYR,OCA2,and SLC45A2 genes were examined in the proband, and verified in her parents by Sanger sequencing.Large deletion or duplication of TYR and OCA2 genes was detected by multiplex ligation-dependent probe amplification (MLPA).A homozygous TYR c.307T>C (p.Cys103Arg)missense mutation was identified in the proband,and both parents were heterozygous carriers.No large deletion or duplication was found in the proband.This mutation was absent in 1000G,ExAC,or HGMD database,and multiple lines of in silico tools supported a deleterious effect.These results suggest that TYR c.307T>C mutation might be responsible for OCA1,and our study further expands the mutation spectrum of OCA1 in the Chinese population.
文摘Objective :To study the gene mutations of homeobox transcription factor (CSX/NKX2.5) associated with a Chinese family with secundum atrial septal defect (ASD). Methods :Polymerase chain reaction and DNA sequencing were used to check all the members in the family with ASD, and single strand conformation polymorphism analysis (SSCP) was used to check 126 normal control people for detecting the mutations of CSX/NKX2.5 gene. Results: Three mutations, G270A(Glu32Lys ), G378A (Glu68Lys)andG390A (Glu72Lys)were identified in CSX/NKX2.5 gene of ASD patients. However, the other members in the family with ASD and the control did not have such gene mutations. Conclusion:These mutations of CSX/NKX2.5 gene, which were identified in a Chinese family, may be one of the secundum ASD etiologic causes .
文摘The population of early-onset Alzheimer's disease(EOAD)accounts for 1%-2%of the total population of Alzheimer's disease,and genetic mutations are more common in EOAD.The first symptom of the patient in the present case report was the decline in memories of recent events,and the disease progressed rapidly in the following 2 years.Genetic testing has revealed the presence of genetic mutations(c.A479G,p.N160S)of ACE,which causes the 160th codon of the ACE protein to change from aspartic acid to serine,and at the same time genotype of apolipoprotein E(APOE)is ε3/ε4.We think that this patient carries the mutation type of the sensitive gene ACE and the risk gene APOE of Alzheimer's disease,and this is the reason why the disease progressed rapidly.Moreover,we discussed ACE genetic mutation's meaning in EOAD progression.
文摘BACKGROUND Autosomal dominant tubulointerstitial kidney disease(ADTKD)is a progressive chronic disease that is inherited in an autosomal dominant fashion.Symptoms include hyperuricemia,gout,interstitial nephritis,renal cysts,and progressive renal damage that can lead to end-stage renal disease.Mutations in the uromodulin gene(UMOD)characterize the ADTKD-UMOD clinical subtype of this disease.To date,>100 UMOD mutations have been identified.Early diagnosis of ADTKD-UMOD is important to treat the disease,slow down disease progression,and facilitate the identification of potentially affected family members.CASE SUMMARY We report a 40-year-old man harboring a novel heterozygous missense mutation in UMOD(c.554G>T;p.Arg185Leu).The patient had hyperuricemia,gout,and chronic kidney disease.The same mutation was detected in his daughter,aunt and cousin.CONCLUSION A single nucleotide substitution in exon 3 of UMOD was responsible for the heterozygous missense mutation(c.554G>T,p.Arg185Leu).
基金support from the National Key Research and Developmental Program of China (No.2018YFC1003603)the National Natural Science Foundation of China (No.81971445).
文摘Congenital bilateral absence of the vas deferens(CBAVD)is observed in 1%–2%of males presenting with infertility and is clearly associated with cystic fibrosis transmembrane conductance regulator(CFTR)mutations.CFTR is one of the most well-known genes related to male fertility.The frequency of CFTR mutations or impaired CFTR expression is increased in men with nonobstructive azoospermia(NOA).CFTR mutations are highly polymorphic and have established ethnic specificity.Compared with F508Del in Caucasians,the p.G970D mutation is reported to be the most frequent CFTR mutation in Chinese patients with cystic fibrosis.However,whether p.G970D participates in male infertility remains unknown.Herein,a loss-of-function CFTR p.G970D missense mutation was identified in a patient with CBAVD and NOA.Subsequent retrospective analysis of 122 Chinese patients with CBAVD showed that the mutation is a common pathogenic mutation(4.1%,5/122),excluding polymorphic sites.Furthermore,we generated model cell lines derived from mouse testes harboring the homozygous Cftr p.G965D mutation equivalent to the CFTR variant in patients.The Cftr p.G965D mutation may be lethal in spermatogonial stem cells and spermatogonia and affect the proliferation of spermatocytes and Sertoli cells.In spermatocyte GC-2(spd)ts(GC2)Cftr p.G965D cells,RNA splicing variants were detected and CFTR expression decreased,which may contribute to the phenotypes associated with impaired spermatogenesis.Thus,this study indicated that the CFTR p.G970D missense mutation might be a pathogenic mutation for CBAVD in Chinese males and associated with impaired spermatogenesis by affecting the proliferation of germ cells.
文摘We have analyzed the exons 13, 16, 21 and 23 of cardiac myosin heavy chain gene in 32 Chinese patients with hypertrophic cardiomyopathy by using PCR-single strand conformation polymorphism (PCR-SSCP) procedure. The result showed an altered SSCP of the exon 13 in one patient. Sequencing analysis revealed that the patient had a G to T transversion in the codon 383, resulting in the substitution of Lys by Asn. Beacause the missense mutation was found at the residue highly conserved through species evolution, this mutation is likely, to be the cause of hypertrophic cardiomyopathy in this patient. This is the first report of a mutant cardiac β-MHC gene in the Chinese population. Also, it is a novel missense mutation of the cardiac β-MHC gene.
基金supported by the National Natural Science Foundation of China(31871262)a Shanghai Municipal Science and Technology Major Project(2018SHZDZX05).
文摘PiT2 is an inorganic phosphate(Pi)transporter whose mutations are linked to primary familial brain calcification(PFBC).PiT2 mainly consists of two ProDom(PD)domains and a large intracellular loop region(loop7).The PD domains are crucial for the Pi transport,but the role of PiT2-loop7 remains unclear.In PFBC patients,mutations in PiT2-loop7 are mainly nonsense or frameshift mutations that probably cause PFBC due to C-PD1131 deletion.To date,six missense mutations have been identified in PiT2-loop7;however,the mechanisms by which these mutations cause PFBC are poorly understood.Here,we found that the p.T390A and p.S434W mutations in PiT2-loop7 decreased the Pi transport activity and cell surface levels of PiT2.Furthermore,we showed that these two mutations attenuated its membrane localization by affecting adenosine monophosphate-activated protein kinase(AMPK)-or protein kinase B(AKT)-mediated PiT2 phosphorylation.In contrast,the p.S121C and p.S601W mutations in the PD domains did not affect PiT2 phosphorylation but rather impaired its substrate-binding abilities.These results suggested that missense mutations in PiT2-loop7 can cause Pi dyshomeostasis by affecting the phosphorylation-regulated cell-surface localization of PiT2.This study helps understand the pathogenesis of PFBC caused by PiT2-loop7 missense mutations and indicates that increasing the phosphorylation levels of PiT2-loop7 could be a promising strategy for developing PFBC therapies.
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.