一例SRY阴性Y-常染色体不平衡易位女性的细胞分子遗传学分析  

Cytogenetic studying in a female carrying SRY negative Y-autosomal unbalanced translocation

作　　者：徐玲玲 周颖[1] 张莉超[1] 王振宇[1] 毛倩倩[1] 李海波 XU Ling-ling;ZHOU Ying;ZHANG Li-chao;WANG Zhen-yu;MAO Qian-qian;LI Hai-bo(Birth Defect Control Laboratory,Ningbo Maternal and Child Health Care Hospital,Ningbo,Zhejiang 315012,China)

机构地区：[1]宁波市妇女儿童医院出生缺陷防治实验室,浙江宁波315012

出　　处：《中国卫生检验杂志》2022年第2期186-188,192,共4页Chinese Journal of Health Laboratory Technology

基　　金：浙江省医药卫生科技计划项目(2020KY282)。

摘　　要：目的联合多种遗传学检测方法对一例SRY阴性的Y-常染色体不平衡易位女性进行遗传学诊断,探讨遗传学诊断结果与临床表型的相关性。方法对一例不孕症女性患者应用常规染色体G显带核型、荧光原位杂交(FISH)及单核苷酸多态性微阵列芯片(SNP-array)进行遗传学分析,并结合父母外周血染色体核型分析染色体变异的遗传方式。结果染色体G显带核型分析46,XX,add(22)(P13),同时患者父亲核型为46,XY,add(22)(P13),表明患者异常染色体源于父亲。未知片段G显带深染,推测可能为Y染色体异染色质,使用DYZ3(Yp11.1-q11.1)和DYZ1(Yq12)2个探针,通过FISH检测明确该异常染色体为Y染色体长臂部分片段与22号染色体短臂连接形成的衍生染色体,即46,XX,add(22)(P13).ish der(22)t(Y;22)pat(DYZ3-,DYZ1+)。涉及Y染色体的易位,断裂位点与临床表型关系密切,特别是涉及SRY、SHOX、AZF等表型相关基因,因此为明确染色体断裂点的具体位置,使用SNP-array进行检测,芯片分析结果未发现全基因组范围内存在明确致病效应的拷贝数改变。结论综合G显带核型、FISH、SNP-array等遗传学检测方法对一例22号染色体短臂附加片段进行明确诊断,Y-22不平衡易位染色体可引起减数分裂中的染色体配对分离异常,可能是患者不孕症的原因。Objective A case of SRY negative Y-autosomal unbalanced translocation was diagnosed by genetic diagnosis combined with multiple genetic testing methods,and the correlation between genetic diagnosis and clinical phenotype was discussed.Methods Conventional chromosome G-banding karyotype and fluorescence in situ hybridization were used in an infertile female patient.Fluorescence in situ hybridization(FISH)and single nucleotide polymorphism array(SNP-array)were used to analyze genetic patterns of chromosomal variation combined with parental peripheral blood karyotypes.Results Karyotype analysis of chromosome G banding showed it was 46,XX,add(22)(P13),and the patient's father karyotype was 46,XY,add(22)(P13),indicating that the abnormal chromosome of the patient originated from his father.The unknown fragment G was deeply stained,which was speculated to be Y chromosome heterochromatin.Two probes DYZ3(Yp11.1-q11.1)and DYZ1(Yq12)were used to confirm that the abnormal chromosome was a derivative chromosome formed by connecting part of the long arm of Y-chromosome with the short arm of chromosome 22 through FISH detection.Namely,46,XX,add(22)(P13).ish der(22)t(Y;22)pat(DYZ3-,DYZ1+).As for Y-chromosome translocations,the break sites are closely related to clinical phenotypes,especially phenotypic related genes such as SRY,SHOX and AZF.Therefore,SNP-array detection was used to determine the specific location of chromosome break points,and no copy number changes with clear pathogenic effects were found in the whole genome by chip analysis.Conclusion Genetic detection methods such as G-banding karyotype,FISH and SNP-array were combined to make a definite diagnosis of the short arm attached fragment of chromosome 22.The Y-22 unbalanced translocation chromosome can cause abnormal chromosome pair separation in meiosis,which may be the cause of the patient's infertility.

关 键 词：染色体核型分析 单核苷酸多态微阵列芯片 荧光原位杂交 

分 类 号：R71[医药卫生—妇产科学]