Turner综合征患者额外小标记染色体的来源与形态研究

目的分析Turner综合征嵌合体核型患者额外小标记染色体(small supernumerary marker chromosomes,sSMC)的来源与形态。方法对1例常规G显带分析核型为45,X[26]/46,X,+mar[43]嵌合体的患者进行荧光原位杂交、高通量全基因组测序、SRY基因Sanger测序分析,明确其sSMC片段来源和存在形态。结果患者G显带核型为45,X[26]/46,X,+mar[43]。荧光原位杂交结果核型为45,X的细胞37个;核型为46,X,+mar的细胞63个。sSMC有两种形态:一种整条染色体两端各可见一个清晰红色信号,提示该sSMC来源于有双着丝粒Y染色体且同源;另一种只见到一个红色信号,提示该sSMC来源于有一个着丝粒Y染色体。C显带显示Y染色体异染色质缺失。Y染色体AZF区微缺失筛查分析SRY存在。SRY基因突变检测未发现异常。高通量测序检测染色体基因组微缺失微重复结果,Y染色体q11.221q12位置存在约42.88 Mb缺失。患者核型最终定为45,X[26]/46,X,del(Y)(q11.22q12)[24]/46,X,pus idic(Y)(q11.22)[19]。结论本例mos 45,X[26]/46,X,+mar[43]Turner综合征患者的sSMC同时存在双着丝粒状、带有着丝粒的染色体小片段两种形态。精确定位sSMC来源和形态,可为遗传咨询和产前诊断提供参考。     

一例性发育异常患儿的遗传学分析CSCD

目的探讨1例性发育异常(disorders of sex development,DSD)患儿的致病原因。方法应用染色体核型分析技术、荧光原位杂交(fluorescence in situ hybridization,FISH)技术、染色体微阵列分析(chromosomal microarray analysis,CMA)技术和性腺组织病理活检技术对患儿进行遗传学检测及致病原因探讨。结果综合各种检测技术,患儿分子细胞核型分析结果为46,X,psu idic(Y)(p11.32)[72]/45,X[28].ish psu idic(Y)(p11.32)(SRY++,DYZ3++).arr[hg19]Yp11.32(118552-512055)×0,Yp11.32p11.31(515916-2640819)×1-2,Yq12(59055438-59336104)×1-2,Yp11.31q11.23(2650425-28799654)×1-2。CMA结果显示在Y染色体短臂的拟常染色体区域1(PAR1)末端存在393.5 kb片段的缺失;约50%的细胞在PAR1区域(Yp11.32p11.31)存在2.1 Mb片段的重复;约50%的细胞在Y染色体Yp11.31q11.23区域存在26.1 Mb片段的重复;约50%的细胞在PAR2区域存在280.6 kb片段的重复。结论46,X,psu idic(Y)(p11.32)[72]/45,X[28]嵌合核型是导致患儿性发育异常的原因。     

三例畸变Y染色体的重组形式及定位分析

目的 对3例畸变Y染色体进行定位分析并确定其重组形式.方法 采用染色体G显带、多重连接依赖探针扩增(multiplex ligation dependent probe amplification,MLPA)、荧光原位杂交(fluorescence in situ hybridization,FISH)、Y染色体多个序列标签位点(sequence tagged site,STS)及Illumina人类全基因组单核苷酸多态性芯片扫描(single nucleotide polymorphisms array,SNP-array)等多种技术.结果 3例患者染色体G显带核型均为46,X,+ mar.MLPA检测发现例1 SRY、ZFY、UTY基因重复;例2 SRY、ZFY基因重复、UTY基因缺失;例3X染色体短臂/Y染色体短臂(X/Yp)、X染色体长臂/Y染色体长臂(X/Yq)亚端粒区域基因拷贝数减少.Y染色体STS分析提示:例1的SRY及Y染色体AZFa区sY84、sY86、AZFb区sY1227存在,但sY1228及AZFc区多个STS缺失,断裂点位于AZFb区sY1227和sY1228之间;例2的SRY及着丝粒区域sY1200存在,其余STS均缺失;例3的SRY及AZF多个STS均存在.SNP-array扫描提示,例1 Yp11.31-p11.2区重复,Yq11.22-q11.23区缺失,缺失片段约为5.18 Mb;例2 Yp11.31-p11.2区重复,重复片段为3.724 Mb,Yq11.21-q11.23区域缺失,缺失约14.644Mb;例3 X/Yp亚端粒区域(PAR) p22.33单拷贝缺失,X/Yq亚端粒区域(PAR) q28单拷贝缺失.FISH分析提示,例1和例2细胞中期原位杂交核型均为46,X,+ mar.ish(Y)(SRY++,DYZ3++,DYZ1-).综合分析:例1和例2的标记染色体均为短臂等臂双着丝粒Y染色体.分子核型:例1为46,X,idic (Y)(q11.23);例2为46,X,idic(Y) (q10);例3为标记染色体为环状Y,核型为46,X,r(Y)(p1 1q12).结论 Y染色体畸变形式多样,选用MLPA、Y染色体STS、FISH、SNP-array等多项技术联合诊断是确定其断裂点及重组形式的重要手段.     

三例额外小标记染色体的细胞及分子遗传学分析

目的对3例微小额外标记染色体(small supernumerary marker chromosomes,sSMC)的来源与结构进行鉴定,探讨其发生机理,为临床遗传咨询提供参考。方法应用染色体显带技术(G带、C带、N带)进行染色体核型分析,基因芯片技术明确sSMC片段的来源和区域,并用荧光原位杂交(fluorescence in situ hybridization,FISH)技术进行验证。结果例1外周血染色体核型为47,XY,+mar,为新发变异,sSMC为双着丝粒双随体结构,芯片结果示未包含已知人类疾病相关致病基因,推测不增加子代表型异常的风险。例2胎儿染色体核型结果为47,XY,+mar[17]/46,XY[33],为新发变异,常规显带技术提示mar上有常染色质,芯片检测结果为arr[hg19]5p12q11.1(45694574-49475697)×3,经FISH验证,明确胎儿sSMC片段含有HCN1基因部分区段的5p12片段。例3胎儿染色体核型为45,XY,-13[25]/46,XY,r(13)[18]/46,XY,-13,+mar[7],夫妻双方拒绝进一步检查。结论传统的显带技术联合分子检测技术能对sSMC的结构及来源进行分析,可明确sSMC的致病性,为临床遗传咨询提供参考。     

一例性发育异常患儿的遗传学分析

目的探讨1例性发育异常(disorders of sex development, DSD)患儿的致病原因。方法应用染色体核型分析技术、荧光原位杂交(fluorescencein situ hybridization, FISH)技术、染色体微阵列分析(chromosomal microarray analysis, CMA)技术和性腺组织病理活检技术对患儿进行遗传学检测及致病原因探讨。结果综合各种检测技术, 患儿分子细胞核型分析结果为46, X, psu idic(Y)(p11.32)[72]/45, X[28]. ish psu idic(Y)(p11.32)(SRY++, DYZ3++). arr[hg19] Yp11.32(118 552-512 055)×0, Yp11.32p11.31(515 916-2 640 819)×1-2, Yq12(59 055 438-59 336 104) ×1-2, Yp11.31q11.23(2 650 425-28 799 654)×1-2。CMA结果显示在Y染色体短臂的拟常染色体区域1(PAR1)末端存在393.5 kb片段的缺失;约...     

SNP芯片技术产前鉴别额外小标记染色体

目的 用SNP芯片技术对1例产前发现的疑难额外小标记染色体(small supernumerary marker chromosome,sSMC)进行鉴定,明确其遗传物质的来源并推测其发生机制.方法 对1例染色体核型分析提示携带来源不明sSMC的胎儿进行SNP芯片全基因组扫描检测,结果用荧光原位杂交技术(fluorescence in situ hybridization,FISH)验证.结果 胎儿染色体核型示46,X,+mar,芯片结果确定sSMC为Yp11.2-11.3重复、Yq11.2区域缺失,FISH结果证明sSMC来源于Y染色体.结论 明确胎儿核型为46,X,idic(Y)(pter→ p11.2∶∶11.2→pter).Yq11.2区的缺失与男性无精症相关.芯片技术可一次性排除23对染色体大于1 Mb的微缺失和重复,明确遗传学机制,适用于疑难病例的鉴别和微缺失重复综合征的产前诊断.     

人类额外小标记染色体的鉴定及其研究价值的探讨

目的 应用荧光原位杂交(fluorescent in situ hybridization,FISH)结合染色体核型分析了解人类额外小标记染色体(small supernumerary marker chromosomes,sSMC)的来源,并探讨其发生机理及应用价值.方法 对3例羊水染色体核型分析结果显示是47,XN,+mar的胎儿羊水细胞用两种探针cepFISH(针对着丝粒)和SubcenM-FISH(针对近着丝粒区域)进行分析.结果 病例1的FISH结果为47,XY,+mar.ish inv dup(22) (q11.1)(D22Z4++,D14/22Z1+,RP11-172D7-),标记染色体完全由异染色质组成,胎儿活产未见异常临床表型.病例2的FISH结果为47,XX,+mar.ish r(10) (p11.2q11.2)(cep10+,RP11 232C13+,RP11-178A10+)[25]/46,XX[10],标记染色体由着丝粒附近的常染色质和异染色质组成,胎儿活产无异常临床表型.病例3的FISH结果为47,XY,+mar.ish inv dup(22) (q11.1)(D22Z4+,D14/22Z1+),标记染色体由异染色质组成,胎儿B超有异常但与此标记染色体关系不明.结论 由于sSMC来源的多样性,给产前诊断带来了巨大的困难.其鉴定需要在传统的显带核型分析基础上结合FISH或者其他分子技术.其特殊的结构也为基因定位、异染色质研究以及基因治疗等提供了非常有价值的研究载体.     

罕见Down-Turner双重综合征的遗传学研究

目的 对1例复杂染色体核型的Down-Turner双重综合征进行分子细胞遗传学分析,以指导临床遗传咨询和诊断.方法 在常规染色体核型分析的基础上,结合荧光原位杂交技术并进行家系遗传分析.结果 1例Down-Turner双重综合征患儿染色体核型确诊为46,X,+mar.ish i(14 0r 22)(p10)(D14Z1/D22Z1+)[32]/47,X,der(X)t(X;21)(p22.3;q11.2),+mar.ish der(X)(D21Z1+,Xpter-).ish i(14 0r 22)(p10)(D14Z1/D22Z1+)[28],其中标记染色体来源于其母亲.结论 Down-Turner双重综合征染色体核型复杂多样,有必要采用常规显带技术、荧光原位杂交技术和家族遗传分析等相结合的方法进行诊断,以便为临床遗传咨询和诊断提供精确的遗传学指导依据.     

环状染色体综合征孕妇的遗传学分析及产前诊断

目的 对2例智力低下的孕妇进行细胞及分子遗传学检测，寻找致病原因，并对其胎儿进行产前诊断。方法 收集2例孕妇的临床资料，对其进行外周血细胞染色体G显带核型分析和（或）染色体微阵列分析（CMA），并对其胎儿进行相应的产前诊断。结果 病例1：孕妇外周血染色体核型为46,XX,r(6)(p25.3q27)[82]/45,XX,-6[11]/46,XX,dic r(6;6)(p25.3q27;p25.3q27)[6]/46,XX,-6,+mar[1],CMA结果为arr[hg19]6p25.3(156,974-302,273)×1,6q27(166,612,359-170,914,297)×1；其胎儿羊水细胞染色体核型为46,XN,CMA结果为arr[hg19]16p11.2(29,591,326-30,177,240)×3。病例2：孕妇外周血染色体核型为46,XX,r(13)(p12q34)[77]/46,XX,dic r(13;13)(p12q34;p12q34)[13]/45,XX,-13[9]/46,XX[1]，未行CMA检测；其胎儿羊水细胞染色体核型为46,XN,CMA结果正常。结论...     

一例9号微小额外标记染色体的遗传学分析

目的结合细胞遗传学与分子遗传学技术探讨一例9号染色体微小额外标记染色体(small supernumerary marker chromosome, sSMC)的遗传学机制。方法因超声发现一例胎儿左心室点状强回声, 无创产前检测提示胎儿8号单体或部分缺失、9号三体、11号单体或部分缺失高风险, 对孕中期血清学筛查提示单项中值倍数值异常的孕妇进行羊水穿刺, 进行染色体G显带核型分析及单核苷酸多态性微阵列(single nucleotide polymorphism array, SNP array)检测。对孕妇进一步进行C显带核型分析和荧光原位杂交(fluorescencein situ hybridization, FISH)检测。结果孕妇染色体G显带核型为47, XX, +mar[20]/46, XX[80], C显带显示sSMC中间深染, 提示为着丝粒区域, 两端浅染, 提示含有常染色质;采用9pter/9qter探针的FISH结合DAPI显带分析结果显示孕妇为47, XX, +mar.ish i(9)(9p10)(9p++)[2]/46, XX[18];SNP array提示孕妇...     

Cytogenetic and molecular characterization of two isodicentric Y chromosomes

We report the results of detailed molecular-cytogenetic studies of two isodicentric Y [idic(Y)] chromosomes identified in patients with complex mosaic karyotypes. We used fluorescence in situ hybridization (FISH) and polymerase chain reaction (PCR) to determine the structure and genetic content of the abnormal chromosomes. In the first patient, classical cytogenetics and FISH analysis with Y chromosome-specific probes showed in peripheral blood lymphocytes a karyotype with 4 cell lines: 45,X[128]/46,X,+idic(Y)(p11.32)[65]/47,XY,+idic(Y)(p11.32)[2]/47,X,+2idic(Y)(p11.32)[1]. No Y chromosome material was found in the removed gonads. For precise characterization of the Yp breakpoint, FISH and fiberFISH analysis, using a telomeric probe and a panel of cosmid probes from the pseudoautosomal region PAR1, was performed. The results showed that the breakpoint maps approximately 1,000 Kb from Ypter. The second idic(Y) chromosome was found in a boy with mild mental retardation, craniofacial anomalies, and the karyotype in lymphocytes 47,X,+idic(Y)(q11.23),+i(Y)(p10)[77]/46,X,+i(Y)(p10)[23]. To our knowledge, such an association has not been previously described. FISH and PCR analysis indicated the presence of at least two copies of the SRY gene in all analyzed cells. Using 17 PCR primers, the Yq breakpoint was shown to map between sY123 (DYS214) and sY121 (DYS212) loci in interval 5O in AZFb region. Possible mechanisms of formation of abnormal Y chromosomes and karyotype-phenotype correlations are discussed.     

Genetic analysis for 2 females carrying idic(Y)(p) and with sex development disorders北大核心CSCD

Objective: To investigate the phenotype-genotype association of isodicentromere Y chromosome by analysis of two female patients carrying the chromosome with sexual development disorders. Methods: The karyotypes of the two patients were determined by application of conventional G banding of peripheral blood samples and fluorescence in situ hybridization (FISH). PCR was applied to detect the presence of SRY gene. Results: Conventional karyotype analysis showed case 1 to be a mosaic: mos. 45,X[38]/46,X,+mar[151]/47,XY,+mar[5]/47,X,+marX2[2]/46,XY[4], FISH showed that 12 different cell lines were presented in the karyotype of case 1 and partial cell lines with SRY gene, the marker is an isodicentromere Y chromosome[idic(Y)(p)]. No mutation was found in the SRY gene. The karyotype of case 2 was mos. 45,X[25]/46,X,+mar[35]. FISH showed the marker to be an idic(Y)(p) without the SRY gene. Conclusion: The karyotype of patients carrying idic(Y)(p) seems unstable, and female patients have the characteristics of short stature and secondary sexual hypoplasia. Karyotype analysis combined with FISH analysis can accurately determine the breakpoint of idic(Y) and identify the types of complex mosaic, which may facilitate genetic counseling and prognosis. © 2016, West China University of Medical Sciences. All rights reserved.     

一例idic(15)来源的嵌合型标记染色体的遗传学分析

目的:应用细胞遗传学和分子生物学检测方法明确1例嵌合型标记染色体患者的核型及其来源。方法:抽取患者的外周血样,进行染色体核型分析、基因芯片检测和荧光原位杂交检测。结果:染色体分析结果显示患者核型为mos 47,XX,+mar [45]/48,XX, +2mar[3]/ 46,XX[52];基因芯片检测结果为arr[hg...     

Complex chromosome 9, 20, and 22 rearrangements in acute lymphoblastic leukemia with duplication of BCR and ABL sequences

Cytogenetic analysis was performed on bone marrow cells from a 28-year-old woman who was diagnosed with acute lymphoblastic leukemia (ALL). Her karyotype was: 46,XX,t(9;22)(q34;q11)[6]/47, XX,+8,t(9;22)(q34;q11)[4]/47,XX,+8,t(9;22)(q34;q11),del(20)(q11)[2]/46, XX,t(9;22)(q34;q11),del[20](q11)[7]/45,XX,der(9)t(9;22)(q34;q11),-20,-22 , +mar1[8]/45,XX,der(9)t(9;22)(q34;q11),-20,-22,+mar2[3]. Both marker chromosomes are dicentric and have the same size and banding pattern but different primary constrictions. Fluorescence in situ hybridization (FISH) demonstrated that both markers were derived from chromosomes 9, 20, and 22. FISH with the bcr/abl probe showed fusion of the BCR gene with the ABL gene; however, this fusion signal was present in duplicate on both marker chromosomes. To our knowledge, duplication of the BCR/ABL fusion signal on a single chromosome arm has not been reported before, except for the extensive amplification of BCR/ABL fusion signals in the leukemic cell line K-562. These data demonstrate that the marker chromosomes are the result of complex genomic rearrangements. At the molecular level, the BCR/ABL fusion gene encodes the p190 fusion protein. Similar findings have never been observed in any case of ALL.     

Molecular and clinical description of a girl with a 46,X,t(Y;4)(q11.2;p16)/45,X,der(4)t(Y;4)(q11.2;p16) karyotype and a small cryptic 4p subtelomeric deletion

We report on a 13-year-old female with short stature, minimal axillary and pubic hair, no breast development, absence of uterus and ovaries, with the following karyotype on lymphocyte cultures: 46,X,t(Y;4)(q11.2;p16)[40]/45,X,der(4)t(Y;4)(q11.2;p16)[10]. Loss of the small derivative Y chromosome in 20% of the cells was also confirmed in skin fibroblast cultures. FISH analyses using Y centromere, SRY, subtelomere XpYp/XqYq, Y and 4 painting probes, confirmed the cytogenetic findings. High-resolution STS analyses using 40 markers covering the Y chromosome did not identify any deletion on the Y. However, de novo absence of the 4p subtelomeric region was noted by FISH, although this deletion was not revealed by Array-CGH at 1 Mb resolution, the last array clone being 0.35 or 1 Mb distal to the 4p FISH probe. The female phenotype of this patient must be due to the loss of the derivative Y chromosomes in some of her cells, especially the gonads, while the 4p subtelomeric deletion does not seem to contribute to her phenotype.     

Isodicentric Y (p11.32) chromosome in an infant with mixed gonadal dysgenesis

Among the structural abnormalities affecting the human Y chromosome, dicentric chromosomes are the most common. A wide spectrum of phenotypes of patients with a dicentric Y chromosome exists, ranging from almost males through mixed gonadal dysgenesis to females with Turner syndrome. Here, we describe an infant with mixed gonadal dysgenesis and mosaic karyotype 45,X/46,X,idic(Y)(qter-->p11.32:p11.32-->qter)/47,X,+2idic(Y) (qter-->p11.32:p11.32-->qter)/47,XYY. This was demonstrated by fluorescence in situ hybridization (FISH) analysis with whole Y chromosome painting (WCP-Y) probe. Molecular studies were performed on genomic DNA extracted from peripheral blood lymphocytes. To examine the sex determined region (SRY), azoospermia factor (AZF) region and deletion in azoospermia gene (DAZ), polymerase chain reaction (PCR) analyses were done with sequence-tagged site (STS) primers of 20 loci along the Y chromosome (SRY, DYS271, DYS148, DYS273, KALY, DYS212, SMCY, DYS215, DYS218, DYS219, DYS221, DYS223, DYS224, DYF51S1, DYS236, DAZ, DYS240), and all tested loci were found positive. Because of the possibility of a mutation in the SRY gene, we analyzed the PCR fragment by DNA sequencing and did not observe any mutation or nucleotide alteration. We present detailed molecular-cytogenetic characterization of a patient with idic(Y)(p11.32), and results are discussed with the previously described patients. As far as we know, this is the fifth report of a 46,X, idic(Y)(p11.32) karyotype and the first presentation with mixed gonadal dysgenesis and isodicentric Y. Since the correlation between phenotype and karyotype is not yet well defined, the clinical reports will be helpful in defining the phenotypic range of this chromosomal abnormality.     

Molecular mapping of an idic(Yp) chromosome in an Ullrich‐Turner patient

We describe a woman with Ullrich‐Turner manifestations and a 45,X/46,X,+mar karyotype. Fluorescence in situ hybridization (FISH) and DNA analysis were carried out in order to determine the origin and structure of the marker. FISH showed that the marker was a Y‐derived dicentric chromosome. The breakpoint at Yq11 (interval 6) was mapped using Southern blotting and polymerase chain reaction (PCR). There were no nucleotide alterations in the SRY conserved domain. Histological analysis of the gonads showed an ovarian‐like stroma with no signs of testicular tissue. These findings indicate that the patient was a mosaic 45,X/46,X,idic(Yp) whose phenotypic expression, including sex determination, appeared to have had more influence from the 45,X cell line. Am. J. Med. Genet. 91:95–98, 2000. © 2000 Wiley‐Liss, Inc.     

Turner综合征患儿标记染色体的来源研究

目的 了解Turner综合征患儿标记染色体的来源，以指导遗传咨询及治疗。方法 在染色体核型分析的基础上，对32例Turner综合征患者进行回顾性分析。对3例含有标记染色体的患儿进一步用荧光原位杂交技术研究标记染色体的来源。结果 3例含有标记染色体的Turner综合征患儿中，确定1例患儿的标记染色体来源于Y染色体，含有性别决定基因；1例来源于X染色体；另外1例未能确定其来源，该标记染色体可能来源于性染色体的其他片段或其他端着丝粒染色体。结论 Turner综合征患者的标记染色体大多来源于性染色体（X染色体、Y染色体），也可能来源于其他端着丝粒染色体。有必要同时应用X染色体和Y染色体特异性探针对Turner综合征患者进行标记染色体的荧光原位杂交分析，以明确标记染色体的来源。     

Evidence of a mechanism for isodicentric chromosome Y formation in a 45,X/46,X,idic(Y)(p11.31)/46,X,del(Y)(p11.31) mosaic karyotype

Abnormalities involving sex chromosomes account for approximately 0.5% of live births. The phenotypes of individuals with mosaic cell lines having structural aberrations of the X and Y chromosomes are variable and hard to accurately predict. Phenotypes associated with sex chromosome mosaicism range from Turner syndrome to males with infertility, and often present with ambiguous genitalia. Previous studies of individuals with an 45,X/46,X,idic(Y)(p11) karyotype suggest that the presence of both cell lines should result from an intermediate, 46,XY cell line. Here we report a 2.5 year old female with phenotypic features of Turner syndrome with an isodicentric Y chromosome and a cell line with a deleted Y with a final karyotype of 45,X/46,X,idic(Y)(p11.31)/46,X,del(Y)(p11.31). Fluorescence in situ hybridization (FISH) mapping of the Y chromosome breakpoint revealed very low percentages of the deleted Y cells, but suggested a potential mechanism for the formation of the isodicentric Y chromosome. To our knowledge, the 46,X,del(Y) intermediate cell line in our patient has not been previously reported in individuals with mosaic sex chromosome structural abnormalities.