BACKGROUND The clinical manifestations of trisomy 7 mosaicism are diverse and nonspecific,so prenatal diagnosis is very difficult.CASE SUMMARY Two pregnant women with abnormal prenatal screening results were included....BACKGROUND The clinical manifestations of trisomy 7 mosaicism are diverse and nonspecific,so prenatal diagnosis is very difficult.CASE SUMMARY Two pregnant women with abnormal prenatal screening results were included.One was a 22-year-old woman(G1P0).At 31st week of gestation,ultrasound revealed that the posterior horn of the left lateral ventricle was 10 mm and the right renal pelvis had a separation of 7 mm.The other pregnant woman was 33 years old(G2P1L1A0),and her fetus was found to have a cardiac malformation at the 24th week of gestation.Copy number variation sequencing,whole-exome sequencing and karyotype analysis were carried out after amniocentesis,and both fetuses were diagnosed with trisomy 7 mosaicism.After parental counseling,one woman continued the pregnancy,and the other woman terminated the pregnancy.CONCLUSION In trisomy 7 mosaicism,the low proportion of trisomy does not lead to abortion,but can result in abnormal fetal development,which can be detected via ultrasound.Therefore,clinicians need to pay more attention to various aspects of fetal growth and development,combining with imaging,cellular,molecular genetics and other methods to perform comprehensive evaluations of fetuses to provide more reliable genetic counseling for pregnant women.展开更多
Genomic mosaicism describes the phenomenon where some but not all cells within a tissue harbor unique genetic mutations.Traditionally,research focused on the impact of genomic mosaicism on clinical phenotype—motivate...Genomic mosaicism describes the phenomenon where some but not all cells within a tissue harbor unique genetic mutations.Traditionally,research focused on the impact of genomic mosaicism on clinical phenotype—motivated by its involvement in cancers and overgrowth syndromes.More recently,we increasingly shifted towards the plethora of neutral mosaic variants that can act as recorders of cellular lineage and environmental exposures.Here,we summarize the current state of the field of genomic mosaicism research with a special emphasis on our current understanding of this phenomenon in brain development and homeostasis.Although the field of genomic mosaicism has a rich history,technological advances in the last decade have changed our approaches and greatly improved our knowledge.We will provide current definitions and an overview of contemporary detection approaches for genomic mosaicism.Finally,we will discuss the impact and utility of genomic mosaicism.展开更多
45X/46XY mosaicism is a rare chromosome disease. The apparent prevalence of males and females with 45X/46XY is 5.6 and 2.1 per 100,000 liveborn males and females. We present a boy who had a developmental delay with hy...45X/46XY mosaicism is a rare chromosome disease. The apparent prevalence of males and females with 45X/46XY is 5.6 and 2.1 per 100,000 liveborn males and females. We present a boy who had a developmental delay with hypospadias. He was referred to pediatric genetics and was diagnosed with 45X/46XY mosaicism by peripheral blood chromosome examination. During serial rehabilitation programs, his speech delay was caught up. But his poor attention and hyperactivity are obvious progressively. We should pay attention to these patients, not only physical conditions but also psychological problems.展开更多
BACKGROUND Turner syndrome(TS)has a variety of different karyotypes,with a wide range of phenotypic features,but the specific karyotype may not always predict the phenotype.TS with Y chromosome mosaicism may have mixe...BACKGROUND Turner syndrome(TS)has a variety of different karyotypes,with a wide range of phenotypic features,but the specific karyotype may not always predict the phenotype.TS with Y chromosome mosaicism may have mixed gonadal dysgenesis,and the mosaicism is related to the potential for gonadoblastoma.CASE SUMMARY In this case report,we report two cases of TS with different karyotypes and gonadal dysgenesis.Patient 1 had obvious virilization,and was positive for the SRY gene,but her karyotype in peripheral blood lymphocytes was 45X.Patient 2 had a mosaic karyotype,45X/46X,dic(Y:Y)(p11.3:p11.2),and the proportion of Y-bearing cells was 50%in peripheral blood lymphocytes,but the patient had normal female external genitalia and streaky gonads,with no genital virilism.Different tissues in the same TS individual may exhibit different ratios of mosaicism.The gonadal determination and differentiation of mosaic TS are primarily dependent on the predominant cell line in the gonads.CONCLUSION In TS patients with virilization,it is necessary to test at least two to three tissues to search for cryptic Y material.展开更多
Chromosome constitution was investigated in adult tetraploid Pacific oyster produced by blocking the first polar body oftriploid eggs which were fertilized with haploid sperms. A high incidence of aneuploid and hetero...Chromosome constitution was investigated in adult tetraploid Pacific oyster produced by blocking the first polar body oftriploid eggs which were fertilized with haploid sperms. A high incidence of aneuploid and heteroploid mosaics were found amongthe offspring. Of 20 individuals identified, only 9 （45%） were eutetraploid which contained 40 chromosomes; 2 （10%） were ane-uploid （hypotetraploid）, which contained 39 and 38 chromosomes, respectively; and 9 （45%） were heteroploid mosaics. One mosaicwas consisted of cells containing 40 and 39 chromosomes, respectiovely （1：1 in cell number）, while the other 8 were consisted ofcells containing chromosomes varying between tetraploid and triploid. It was also interesting to note that 3 mosaics even containedsome diploid cells with 20 chromosomes. A certain number of cells of 2 tetraploids and 8 mosaics spread with 32-37 well-scatteredand some clumped chromosomes at metaphase. The percentage of aneuploid cells with chromosomes varying between triploid andtetraploid correlated significantly with that of heteroploid mosaics cells with clumping chromosomes （P〈0.05）. Our findings sug-gested that reversion existed in both tetraploid and triploid oyster and chromosome clumping may underline the chromosome elimi-nation in tetraploid oyster. It seems that the reversing cells, at least some of them, continuously eliminate their chromosomes until themost stable diploid state is established.展开更多
Chorionic villi and fetal tissues from 50 pathological human conceptions at gestational weeks 9-40 were cultured and cytogenetically analyzed to explore the existence of chromosomal mosaicism confined to the extraembr...Chorionic villi and fetal tissues from 50 pathological human conceptions at gestational weeks 9-40 were cultured and cytogenetically analyzed to explore the existence of chromosomal mosaicism confined to the extraembryonic tissues and to clarify the relationship between confined placental mosaicism and adverse outcome of pregnancy. Chorionic villi and fetal tissues from 12 second trimester gestations terminated for social reasons served as a control group. In two pathological gestations, true mosaicism was found exclusively in chorionic cells and could not be confirmed in cells derived from the fetal tissues. One of these was severely growth retarded. Concordant results were obtained in all other cases.展开更多
BACKGROUND Confined placental mosaicism(CPM)is one of the major reasons for discrepancies between the results of non-invasive prenatal testing(NIPT)and fetal karyotype analysis.CASE SUMMARY We encountered a primiparou...BACKGROUND Confined placental mosaicism(CPM)is one of the major reasons for discrepancies between the results of non-invasive prenatal testing(NIPT)and fetal karyotype analysis.CASE SUMMARY We encountered a primiparous singleton pregnant woman with a rare CPM consisting of 47,XY,+21;47,XXY;and 46,XY,who obtained a false-positive result on NIPT with a high risk for trisomy 21.Copy-number variation sequencing on amniotic fluid cells,fetal tissue,and placental biopsies showed that the fetal karyotype was 47,XXY,while the placenta was a rare mosaic of 47,XY,+21;47,XXY;and 46,XY.CONCLUSION The patient had a rare CPM consisting of 47,XY,+21;47,XXY;and 46,XY,which caused a discrepancy between the result of NIPT and the actual fetal karyotype.It is important to remember that NIPT is a screening test,not a diagnostic test.Any positive result should be confirmed with invasive testing,and routine ultrasound examination is still necessary after a negative result.展开更多
Pigmentary mosaicism is proposed to encompass all pigment anomalies caused by chromosomal mosaicism. The concept includes, not only pigment anomalies following the lines of Blaschko, but also pigmentary disorders with...Pigmentary mosaicism is proposed to encompass all pigment anomalies caused by chromosomal mosaicism. The concept includes, not only pigment anomalies following the lines of Blaschko, but also pigmentary disorders with phylloid, checkerboard and patchy pigmentation without midline separation. The representative disorders are hypomelanosis of Ito(pigmentary mosaicism of hypopigmented or Ito type), linear and whorled nevoid hypermelanosis(pigmentary mosaicism of hyperpigmented type), pigmentary mosaicism of hypopigmented and hyperpigmented type, and phylloid hypo- and hypermelanosis. Pigmentary mosaicism is nowadays recognized as a pigmentary disorder caused by somatic chromosomal abnormalities disrupting or accelerating the function of pigmentary genes. Affected individuals with pigmentary mosaicism commonly have multiple congenital abnormalities, developmental delays and/or mental retardation. However, the complication is not a syndrome because functional loss or acquisition due to various chromosomal abnormalities induces pigment abnormalities and specific complications. Cytogenetic abnormalities, including polyploidy, aneuploidy, deletions, insertions and translocations, are associated with almost any chromosome and tissue-limited mosaicism for chromosome abnormalities. Cytogenetic find-ings in cases with the phylloid pattern demonstrate the obvious causal relationship between phylloid hypomelanosis and mosaic trisomy 13. The pattern of cutaneous mosaicism depends on the trajectory of migration and proliferation during embryogenesis. The chromosomal regions of hot breakpoints in pigmentary mosaicism may contain pigmentation-associated genes. The accumulation of relationships between cases and chromosomal analyses may provide the opportunity to identify and understand the pigmentation-associated genes because more than 800 phenotypic alleles are known in the mice models of pigmentary anomalies and not all color loci have been identified. Here, we summarize the clinical features of pigmentary mosaicism and specific forms of phylloid hypo- and hypermelanosis.展开更多
BACKGROUND KBG syndrome is likely underdiagnosed because of mild and non-specific features in some affected patients especially before the upper permanent central incisors eruption at about the age of 7-8 years.Somati...BACKGROUND KBG syndrome is likely underdiagnosed because of mild and non-specific features in some affected patients especially before the upper permanent central incisors eruption at about the age of 7-8 years.Somatic mosaicisms are usually recognized in the parents only after a typically affected son is diagnosed with KBG syndrome.We describe for the first time the mosaicism of a novel variant in a child with a mild KBG phenotype.CASE SUMMARY Our patient presented at 24 mo of age with short stature,hand abnormalities,facial dysmorphism and mild developmental delay.Pituitary hypoplasia and central hypothyroidism were also detected.By next generation sequencing(NGS)analysis we found a novel deletion in the ANKRD11 gene(c.4880_4893del.),that can be classified as likely pathogenic for the syndrome,with the percentage of mutated allele of 36%.We considered this finding as causative of the mild and non-specific phenotype for KBG syndrome in our patient,as previously reported in adults.A heterozygous variant in HESX1 gene,classified as variant of uncertain significance,but suspected of causing pituitary hypoplasia and hormonal deficiency,was also found.The patient started levothyroxine and growth hormone treatment.CONCLUSION The increased use of NGS analysis may expand the phenotypic spectrum of KBG syndrome because it allows genetic diagnosis of somatic mosaicisms also in children.展开更多
Assisted hatching(AH)is commonly performed before trophectoderm(TE)biopsy for preimplantation genetic testing for aneuploidy(PGT-A),yet whether AH timing influences the detection of chromosomal mosaicism remains uncer...Assisted hatching(AH)is commonly performed before trophectoderm(TE)biopsy for preimplantation genetic testing for aneuploidy(PGT-A),yet whether AH timing influences the detection of chromosomal mosaicism remains uncertain.Beyond timing,procedural choices in PGT-A must balance diagnostic yield against potential harm from additional handling(e.g.,repeat TE biopsy or cryopreservation steps),as underscored by a recent systematic review and meta-analysis[1].展开更多
Twin pregnancy with mosaic partial hydatidiform mole （PHM） and survival of two healthy fetuses following in vitro fertilization and embryos transfer （IVF-ET） is a rare situation and is considered a challenge for m...Twin pregnancy with mosaic partial hydatidiform mole （PHM） and survival of two healthy fetuses following in vitro fertilization and embryos transfer （IVF-ET） is a rare situation and is considered a challenge for management. A 32-year-old Chinese woman conceived twin pregnancy following IVF-ET. At 22 weeks＇ gestation, an additional intrauterine echogenic mass with features of PHM were shown by successive ultrasound examinations. At 35 weeks＇ gestation, two live male infants and two placentas were delivered by caesarean section （CS）. Histologic examination of the abnormal placenta confirmed mosaic PHM. Genetic study showed the abnormal placental mosaicism （expressed in molar-69XXY and normal vili-46XY）, co-existing with a hypospadia new-born （46XY） in one amniotic sac. However, the other one was normal. Serial serum β-hCG levels showed a declining trend and serum β-human chorionic gonadotropin （hCG） were undetectable at 6 months after delivery. The case demonstrated that it is possible to prolonged gestation by PHM under close surveillance during the entire pregnancy.展开更多
Although chromosomal mosaic embryos detected by trophectoderm(TE)biopsy offer healthy embryos available for transfer,high-resolution postnatal karyotyping and chromosome testing of the transferred embryos are insuffic...Although chromosomal mosaic embryos detected by trophectoderm(TE)biopsy offer healthy embryos available for transfer,high-resolution postnatal karyotyping and chromosome testing of the transferred embryos are insufficient.Here,we applied single-cell multi-omics sequencing for seven infants with blastula chromosomal mosaicism detected by TE biopsy.The chromosome ploidy was examined by single-cell genome analysis,with the cellular identity being identified by single-cell transcriptome analysis.A total of 1616 peripheral leukocytes from seven infants with embryonic chromosomal mosaicism and three control ones with euploid TE biopsy were analyzed.A small number of blood cells showed copy number alterations(CNAs)on seemingly random locations at a frequency of 0%-2.5%per infant.However,none of the cells showed CNAs that were the same as those of the corresponding TE biopsies.The blastula chromosomal mosaicism may be fully self-corrected,probably through the selective loss of the aneuploid cells during development,and the transferred embryos can be born as euploid infants without mosaic CNAs corresponding to the TE biopsies.The results provide a new reference for the evaluations of transferring chromosomal mosaic embryos in certain situations.展开更多
In the case of a previous offspring with trisomy 21, recurrence risk for Down syndrome is about 1%. It may be due to chance, but the possibility of germline mosaicism for trisomy 21 in one of the parents has important...In the case of a previous offspring with trisomy 21, recurrence risk for Down syndrome is about 1%. It may be due to chance, but the possibility of germline mosaicism for trisomy 21 in one of the parents has important implications for the recurrence. Here we report a young healthy mother, who has a second pregnancy of trisomy 21.展开更多
China and Nepal deepen cooperation to promote traditional medicine across the Himalayan region.THE Himalayan region features a rich mosaic of cultures that are distinct yet deeply intertwined.Traditional medicine,a co...China and Nepal deepen cooperation to promote traditional medicine across the Himalayan region.THE Himalayan region features a rich mosaic of cultures that are distinct yet deeply intertwined.Traditional medicine,a common treasure of human civilization,has deep roots in this region.展开更多
Jute is the golden fiber crop of Bangladesh. Viral and Nemic diseases are the major threats to fiber crops, and the fiber yield decreases drastically as the disease infection increases. An experiment was conducted to ...Jute is the golden fiber crop of Bangladesh. Viral and Nemic diseases are the major threats to fiber crops, and the fiber yield decreases drastically as the disease infection increases. An experiment was conducted to screen and evaluate ten Jute and allied fiber varieties i.e. BJRI Kenaf-4, BJRI Kenaf-3, HS-95 (Kenaf), HS-24 (Mesta pat), HC-2 (Kenaf), BJRI Deshi pat-8, BJRI Deshi pat-7, BJRI Deshi pat-5, BJRI Deshi pat-6 and CVL-1 against mosaic virus and root-knot nematode disease. It was done in RCBD design with three replications at Sher-e-Bangla Agricultural University (SAU) central farm, Dhaka-1207, from June 2018 to March 2019. In the case of viral infection, variety 4 (HS-24 (Mesta pat)) showed maximum virus incidence (23.11%), whereas variety 2 (BJRI Kenaf-3) had no virus evidence. The most susceptible nematode-infected variety was found in varieties 5 (HC-2 (Kenaf)) and 9 (BJRI Deshi pat-6), which showed 80% incidence, whereas variety 2 (BJRI Kenaf-3) was highly resistance. The growth and yield results showed a significant (0.05%) reduction of plant height (cm) and fiber weight (t/ha) with an increase in the percentage of virus and nematode incidence against all varieties. The highest fiber weight (1.47 t/ha) and the lowest viral (0%) and nemic infection (0%) were found in variety 2 (BJRI Kenaf-3), which showed better performance compared to other varieties. These results revealed that variety 2 (BJRI Kenaf-3) had the best variety in the present study.展开更多
Soybean mosaic virus(SMV)poses a substantial threat to the yield and quality of soybean(Glycine max(L.)Merr.),leading to significant economic losses in soybean production.However,the mining of SMVresistance loci and t...Soybean mosaic virus(SMV)poses a substantial threat to the yield and quality of soybean(Glycine max(L.)Merr.),leading to significant economic losses in soybean production.However,the mining of SMVresistance loci and the exploration of the underlying disease resistance mechanisms remain relatively limited.MicroRNAs(miRNAs)are a class of post-transcriptional regulators that play a pivotal role in modulating plant growth,development and responding to various stresses.In this study,we demonstrated the function of the “miR398c/d-GmCSDs”module between soybean resistant and susceptible varieties,focusing on its differential regulatory roles in SMV infection.Specifically,SMV infection downregulated gma-miR398c/d expression in the resistant variety(Qihuang 1,QH),while upregulated them in the susceptible variety(Nannong 1138-2,NN).Transient expression assay in N.benthamiana confirmed that gma-miR398c/d can target six superoxide dismutase(SOD)family genes,which responded to SMV infection in both varieties.Stable overexpression of Gma-MIR398c/d in soybean or inhibition of the corresponding target genes’expression via Bean pod mottle virus(BPMV)-induced gene silencing(VIGS)led to reduced H_(2)O_(2)content and thereby promoted SMV infection.Conversely,plants overexpressing the target genes exhibited the opposite phenotypes.The functions of gma-miR398c/d and their target genes were further validated in N.benthamiana through transient co-expression with SMV infectious clone(pSC7-GFP),indicating that gma-miR398c/d negatively regulated soybean resistance to SMV,while the target genes positively contributed to disease resistance.Collectively,our findings provide novel insights into the regulatory mechanisms underlying soybean resistance to SMV.展开更多
Using nine ice-tethered buoys deployed across the marginal ice zone(MIZ)and pack ice zone(PIZ)north of the Laptev Sea during the expedition of the Multidisciplinary drifting Observatory for the Study of Arctic Climate...Using nine ice-tethered buoys deployed across the marginal ice zone(MIZ)and pack ice zone(PIZ)north of the Laptev Sea during the expedition of the Multidisciplinary drifting Observatory for the Study of Arctic Climate(MOSAiC)in 2019-2020,we characterized the spatiotemporal variations in sea ice kinematics and deformation between October 2019 and July 2020 in the Transpolar Drift(TPD).From October to November,the buoys were in the upstream area of the TPD;spatial variations of deformation rates were significantly correlated with initial ice thickness(R=−0.84,P<0.05).From December 2019 to March 2020,the buoys were in the high Arctic and the ice cover was consolidated;heterogeneity in ice kinematics as measured across the buoys reduced by 65%.From April to May 2020,the buoys were in the downstream TPD;amplified spatial variations in ice kinematics were observed.This is because two buoys had drifted over the shallow waters north of Svalbard earlier;trajectory-stretching exponents derived from the data from these two buoys indicate deformation rates(10.6 d^(−1))that were about twice those in the deep basin(4.2 d^(−1)).By June 2020,a less consolidated ice pack and enhanced tidal forcing in the Fram Strait MIZ resulted in ice deformation with a semi-diurnal power spectral density of>0.25 d^(−1),which is about 1.5 times that in PIZ.Therefore,in both the upstream and downstream regions of the TPD,the transition between the MIZ and the PIZ contributes to the spatial and seasonal variations of sea ice motion and deformation.The results from this study can be used to support the characterization of the momentum balance and influencing factors during the ice advection along the TPD,which is a crucial corridor for Arctic sea ice outflow to the north Atlantic Ocean.展开更多
文摘BACKGROUND The clinical manifestations of trisomy 7 mosaicism are diverse and nonspecific,so prenatal diagnosis is very difficult.CASE SUMMARY Two pregnant women with abnormal prenatal screening results were included.One was a 22-year-old woman(G1P0).At 31st week of gestation,ultrasound revealed that the posterior horn of the left lateral ventricle was 10 mm and the right renal pelvis had a separation of 7 mm.The other pregnant woman was 33 years old(G2P1L1A0),and her fetus was found to have a cardiac malformation at the 24th week of gestation.Copy number variation sequencing,whole-exome sequencing and karyotype analysis were carried out after amniocentesis,and both fetuses were diagnosed with trisomy 7 mosaicism.After parental counseling,one woman continued the pregnancy,and the other woman terminated the pregnancy.CONCLUSION In trisomy 7 mosaicism,the low proportion of trisomy does not lead to abortion,but can result in abnormal fetal development,which can be detected via ultrasound.Therefore,clinicians need to pay more attention to various aspects of fetal growth and development,combining with imaging,cellular,molecular genetics and other methods to perform comprehensive evaluations of fetuses to provide more reliable genetic counseling for pregnant women.
基金support from the Boettcher Foundation and the National Institutes of Health(1K99HD111686).
文摘Genomic mosaicism describes the phenomenon where some but not all cells within a tissue harbor unique genetic mutations.Traditionally,research focused on the impact of genomic mosaicism on clinical phenotype—motivated by its involvement in cancers and overgrowth syndromes.More recently,we increasingly shifted towards the plethora of neutral mosaic variants that can act as recorders of cellular lineage and environmental exposures.Here,we summarize the current state of the field of genomic mosaicism research with a special emphasis on our current understanding of this phenomenon in brain development and homeostasis.Although the field of genomic mosaicism has a rich history,technological advances in the last decade have changed our approaches and greatly improved our knowledge.We will provide current definitions and an overview of contemporary detection approaches for genomic mosaicism.Finally,we will discuss the impact and utility of genomic mosaicism.
文摘45X/46XY mosaicism is a rare chromosome disease. The apparent prevalence of males and females with 45X/46XY is 5.6 and 2.1 per 100,000 liveborn males and females. We present a boy who had a developmental delay with hypospadias. He was referred to pediatric genetics and was diagnosed with 45X/46XY mosaicism by peripheral blood chromosome examination. During serial rehabilitation programs, his speech delay was caught up. But his poor attention and hyperactivity are obvious progressively. We should pay attention to these patients, not only physical conditions but also psychological problems.
文摘BACKGROUND Turner syndrome(TS)has a variety of different karyotypes,with a wide range of phenotypic features,but the specific karyotype may not always predict the phenotype.TS with Y chromosome mosaicism may have mixed gonadal dysgenesis,and the mosaicism is related to the potential for gonadoblastoma.CASE SUMMARY In this case report,we report two cases of TS with different karyotypes and gonadal dysgenesis.Patient 1 had obvious virilization,and was positive for the SRY gene,but her karyotype in peripheral blood lymphocytes was 45X.Patient 2 had a mosaic karyotype,45X/46X,dic(Y:Y)(p11.3:p11.2),and the proportion of Y-bearing cells was 50%in peripheral blood lymphocytes,but the patient had normal female external genitalia and streaky gonads,with no genital virilism.Different tissues in the same TS individual may exhibit different ratios of mosaicism.The gonadal determination and differentiation of mosaic TS are primarily dependent on the predominant cell line in the gonads.CONCLUSION In TS patients with virilization,it is necessary to test at least two to three tissues to search for cryptic Y material.
文摘Chromosome constitution was investigated in adult tetraploid Pacific oyster produced by blocking the first polar body oftriploid eggs which were fertilized with haploid sperms. A high incidence of aneuploid and heteroploid mosaics were found amongthe offspring. Of 20 individuals identified, only 9 （45%） were eutetraploid which contained 40 chromosomes; 2 （10%） were ane-uploid （hypotetraploid）, which contained 39 and 38 chromosomes, respectively; and 9 （45%） were heteroploid mosaics. One mosaicwas consisted of cells containing 40 and 39 chromosomes, respectiovely （1：1 in cell number）, while the other 8 were consisted ofcells containing chromosomes varying between tetraploid and triploid. It was also interesting to note that 3 mosaics even containedsome diploid cells with 20 chromosomes. A certain number of cells of 2 tetraploids and 8 mosaics spread with 32-37 well-scatteredand some clumped chromosomes at metaphase. The percentage of aneuploid cells with chromosomes varying between triploid andtetraploid correlated significantly with that of heteroploid mosaics cells with clumping chromosomes （P〈0.05）. Our findings sug-gested that reversion existed in both tetraploid and triploid oyster and chromosome clumping may underline the chromosome elimi-nation in tetraploid oyster. It seems that the reversing cells, at least some of them, continuously eliminate their chromosomes until themost stable diploid state is established.
文摘Chorionic villi and fetal tissues from 50 pathological human conceptions at gestational weeks 9-40 were cultured and cytogenetically analyzed to explore the existence of chromosomal mosaicism confined to the extraembryonic tissues and to clarify the relationship between confined placental mosaicism and adverse outcome of pregnancy. Chorionic villi and fetal tissues from 12 second trimester gestations terminated for social reasons served as a control group. In two pathological gestations, true mosaicism was found exclusively in chorionic cells and could not be confirmed in cells derived from the fetal tissues. One of these was severely growth retarded. Concordant results were obtained in all other cases.
基金Supported by the 345 Talent Project of Shengjing Hospital,No.M0298.
文摘BACKGROUND Confined placental mosaicism(CPM)is one of the major reasons for discrepancies between the results of non-invasive prenatal testing(NIPT)and fetal karyotype analysis.CASE SUMMARY We encountered a primiparous singleton pregnant woman with a rare CPM consisting of 47,XY,+21;47,XXY;and 46,XY,who obtained a false-positive result on NIPT with a high risk for trisomy 21.Copy-number variation sequencing on amniotic fluid cells,fetal tissue,and placental biopsies showed that the fetal karyotype was 47,XXY,while the placenta was a rare mosaic of 47,XY,+21;47,XXY;and 46,XY.CONCLUSION The patient had a rare CPM consisting of 47,XY,+21;47,XXY;and 46,XY,which caused a discrepancy between the result of NIPT and the actual fetal karyotype.It is important to remember that NIPT is a screening test,not a diagnostic test.Any positive result should be confirmed with invasive testing,and routine ultrasound examination is still necessary after a negative result.
文摘Pigmentary mosaicism is proposed to encompass all pigment anomalies caused by chromosomal mosaicism. The concept includes, not only pigment anomalies following the lines of Blaschko, but also pigmentary disorders with phylloid, checkerboard and patchy pigmentation without midline separation. The representative disorders are hypomelanosis of Ito(pigmentary mosaicism of hypopigmented or Ito type), linear and whorled nevoid hypermelanosis(pigmentary mosaicism of hyperpigmented type), pigmentary mosaicism of hypopigmented and hyperpigmented type, and phylloid hypo- and hypermelanosis. Pigmentary mosaicism is nowadays recognized as a pigmentary disorder caused by somatic chromosomal abnormalities disrupting or accelerating the function of pigmentary genes. Affected individuals with pigmentary mosaicism commonly have multiple congenital abnormalities, developmental delays and/or mental retardation. However, the complication is not a syndrome because functional loss or acquisition due to various chromosomal abnormalities induces pigment abnormalities and specific complications. Cytogenetic abnormalities, including polyploidy, aneuploidy, deletions, insertions and translocations, are associated with almost any chromosome and tissue-limited mosaicism for chromosome abnormalities. Cytogenetic find-ings in cases with the phylloid pattern demonstrate the obvious causal relationship between phylloid hypomelanosis and mosaic trisomy 13. The pattern of cutaneous mosaicism depends on the trajectory of migration and proliferation during embryogenesis. The chromosomal regions of hot breakpoints in pigmentary mosaicism may contain pigmentation-associated genes. The accumulation of relationships between cases and chromosomal analyses may provide the opportunity to identify and understand the pigmentation-associated genes because more than 800 phenotypic alleles are known in the mice models of pigmentary anomalies and not all color loci have been identified. Here, we summarize the clinical features of pigmentary mosaicism and specific forms of phylloid hypo- and hypermelanosis.
文摘BACKGROUND KBG syndrome is likely underdiagnosed because of mild and non-specific features in some affected patients especially before the upper permanent central incisors eruption at about the age of 7-8 years.Somatic mosaicisms are usually recognized in the parents only after a typically affected son is diagnosed with KBG syndrome.We describe for the first time the mosaicism of a novel variant in a child with a mild KBG phenotype.CASE SUMMARY Our patient presented at 24 mo of age with short stature,hand abnormalities,facial dysmorphism and mild developmental delay.Pituitary hypoplasia and central hypothyroidism were also detected.By next generation sequencing(NGS)analysis we found a novel deletion in the ANKRD11 gene(c.4880_4893del.),that can be classified as likely pathogenic for the syndrome,with the percentage of mutated allele of 36%.We considered this finding as causative of the mild and non-specific phenotype for KBG syndrome in our patient,as previously reported in adults.A heterozygous variant in HESX1 gene,classified as variant of uncertain significance,but suspected of causing pituitary hypoplasia and hormonal deficiency,was also found.The patient started levothyroxine and growth hormone treatment.CONCLUSION The increased use of NGS analysis may expand the phenotypic spectrum of KBG syndrome because it allows genetic diagnosis of somatic mosaicisms also in children.
文摘Assisted hatching(AH)is commonly performed before trophectoderm(TE)biopsy for preimplantation genetic testing for aneuploidy(PGT-A),yet whether AH timing influences the detection of chromosomal mosaicism remains uncertain.Beyond timing,procedural choices in PGT-A must balance diagnostic yield against potential harm from additional handling(e.g.,repeat TE biopsy or cryopreservation steps),as underscored by a recent systematic review and meta-analysis[1].
基金This work was supported by grants from the National Natural Science Foundation of China （No. 81100445）, Talents Project of Beijing Health Bureau （No. 2009-2-11） and the Basic and Clinical Research Cooperation Fund of Capital Medical University （No. 11JL54）.
文摘Twin pregnancy with mosaic partial hydatidiform mole （PHM） and survival of two healthy fetuses following in vitro fertilization and embryos transfer （IVF-ET） is a rare situation and is considered a challenge for management. A 32-year-old Chinese woman conceived twin pregnancy following IVF-ET. At 22 weeks＇ gestation, an additional intrauterine echogenic mass with features of PHM were shown by successive ultrasound examinations. At 35 weeks＇ gestation, two live male infants and two placentas were delivered by caesarean section （CS）. Histologic examination of the abnormal placenta confirmed mosaic PHM. Genetic study showed the abnormal placental mosaicism （expressed in molar-69XXY and normal vili-46XY）, co-existing with a hypospadia new-born （46XY） in one amniotic sac. However, the other one was normal. Serial serum β-hCG levels showed a declining trend and serum β-human chorionic gonadotropin （hCG） were undetectable at 6 months after delivery. The case demonstrated that it is possible to prolonged gestation by PHM under close surveillance during the entire pregnancy.
基金the National Key R&D Program of China(Grant No.2018YFC1003100).
文摘Although chromosomal mosaic embryos detected by trophectoderm(TE)biopsy offer healthy embryos available for transfer,high-resolution postnatal karyotyping and chromosome testing of the transferred embryos are insufficient.Here,we applied single-cell multi-omics sequencing for seven infants with blastula chromosomal mosaicism detected by TE biopsy.The chromosome ploidy was examined by single-cell genome analysis,with the cellular identity being identified by single-cell transcriptome analysis.A total of 1616 peripheral leukocytes from seven infants with embryonic chromosomal mosaicism and three control ones with euploid TE biopsy were analyzed.A small number of blood cells showed copy number alterations(CNAs)on seemingly random locations at a frequency of 0%-2.5%per infant.However,none of the cells showed CNAs that were the same as those of the corresponding TE biopsies.The blastula chromosomal mosaicism may be fully self-corrected,probably through the selective loss of the aneuploid cells during development,and the transferred embryos can be born as euploid infants without mosaic CNAs corresponding to the TE biopsies.The results provide a new reference for the evaluations of transferring chromosomal mosaic embryos in certain situations.
文摘In the case of a previous offspring with trisomy 21, recurrence risk for Down syndrome is about 1%. It may be due to chance, but the possibility of germline mosaicism for trisomy 21 in one of the parents has important implications for the recurrence. Here we report a young healthy mother, who has a second pregnancy of trisomy 21.
文摘China and Nepal deepen cooperation to promote traditional medicine across the Himalayan region.THE Himalayan region features a rich mosaic of cultures that are distinct yet deeply intertwined.Traditional medicine,a common treasure of human civilization,has deep roots in this region.
文摘Jute is the golden fiber crop of Bangladesh. Viral and Nemic diseases are the major threats to fiber crops, and the fiber yield decreases drastically as the disease infection increases. An experiment was conducted to screen and evaluate ten Jute and allied fiber varieties i.e. BJRI Kenaf-4, BJRI Kenaf-3, HS-95 (Kenaf), HS-24 (Mesta pat), HC-2 (Kenaf), BJRI Deshi pat-8, BJRI Deshi pat-7, BJRI Deshi pat-5, BJRI Deshi pat-6 and CVL-1 against mosaic virus and root-knot nematode disease. It was done in RCBD design with three replications at Sher-e-Bangla Agricultural University (SAU) central farm, Dhaka-1207, from June 2018 to March 2019. In the case of viral infection, variety 4 (HS-24 (Mesta pat)) showed maximum virus incidence (23.11%), whereas variety 2 (BJRI Kenaf-3) had no virus evidence. The most susceptible nematode-infected variety was found in varieties 5 (HC-2 (Kenaf)) and 9 (BJRI Deshi pat-6), which showed 80% incidence, whereas variety 2 (BJRI Kenaf-3) was highly resistance. The growth and yield results showed a significant (0.05%) reduction of plant height (cm) and fiber weight (t/ha) with an increase in the percentage of virus and nematode incidence against all varieties. The highest fiber weight (1.47 t/ha) and the lowest viral (0%) and nemic infection (0%) were found in variety 2 (BJRI Kenaf-3), which showed better performance compared to other varieties. These results revealed that variety 2 (BJRI Kenaf-3) had the best variety in the present study.
基金supported by the National Key Research and Development Program of China(2022YFF1001502)Jiangsu Collaborative Innovation Center for Modern Crop Production(JCIC-MCP)Major Projects of Technological Innovation 2030(2023ZD04037).
文摘Soybean mosaic virus(SMV)poses a substantial threat to the yield and quality of soybean(Glycine max(L.)Merr.),leading to significant economic losses in soybean production.However,the mining of SMVresistance loci and the exploration of the underlying disease resistance mechanisms remain relatively limited.MicroRNAs(miRNAs)are a class of post-transcriptional regulators that play a pivotal role in modulating plant growth,development and responding to various stresses.In this study,we demonstrated the function of the “miR398c/d-GmCSDs”module between soybean resistant and susceptible varieties,focusing on its differential regulatory roles in SMV infection.Specifically,SMV infection downregulated gma-miR398c/d expression in the resistant variety(Qihuang 1,QH),while upregulated them in the susceptible variety(Nannong 1138-2,NN).Transient expression assay in N.benthamiana confirmed that gma-miR398c/d can target six superoxide dismutase(SOD)family genes,which responded to SMV infection in both varieties.Stable overexpression of Gma-MIR398c/d in soybean or inhibition of the corresponding target genes’expression via Bean pod mottle virus(BPMV)-induced gene silencing(VIGS)led to reduced H_(2)O_(2)content and thereby promoted SMV infection.Conversely,plants overexpressing the target genes exhibited the opposite phenotypes.The functions of gma-miR398c/d and their target genes were further validated in N.benthamiana through transient co-expression with SMV infectious clone(pSC7-GFP),indicating that gma-miR398c/d negatively regulated soybean resistance to SMV,while the target genes positively contributed to disease resistance.Collectively,our findings provide novel insights into the regulatory mechanisms underlying soybean resistance to SMV.
基金supported by the National Key Research and Development Program of China(Grant no.2021YFC2803304)the National Natural Science Foundation of China(Grant nos.52192691 and 52192690)the Program of Shanghai Academic/Technology Research Leader(Grant no.22XD1403600).
文摘Using nine ice-tethered buoys deployed across the marginal ice zone(MIZ)and pack ice zone(PIZ)north of the Laptev Sea during the expedition of the Multidisciplinary drifting Observatory for the Study of Arctic Climate(MOSAiC)in 2019-2020,we characterized the spatiotemporal variations in sea ice kinematics and deformation between October 2019 and July 2020 in the Transpolar Drift(TPD).From October to November,the buoys were in the upstream area of the TPD;spatial variations of deformation rates were significantly correlated with initial ice thickness(R=−0.84,P<0.05).From December 2019 to March 2020,the buoys were in the high Arctic and the ice cover was consolidated;heterogeneity in ice kinematics as measured across the buoys reduced by 65%.From April to May 2020,the buoys were in the downstream TPD;amplified spatial variations in ice kinematics were observed.This is because two buoys had drifted over the shallow waters north of Svalbard earlier;trajectory-stretching exponents derived from the data from these two buoys indicate deformation rates(10.6 d^(−1))that were about twice those in the deep basin(4.2 d^(−1)).By June 2020,a less consolidated ice pack and enhanced tidal forcing in the Fram Strait MIZ resulted in ice deformation with a semi-diurnal power spectral density of>0.25 d^(−1),which is about 1.5 times that in PIZ.Therefore,in both the upstream and downstream regions of the TPD,the transition between the MIZ and the PIZ contributes to the spatial and seasonal variations of sea ice motion and deformation.The results from this study can be used to support the characterization of the momentum balance and influencing factors during the ice advection along the TPD,which is a crucial corridor for Arctic sea ice outflow to the north Atlantic Ocean.
