应用单核苷酸多态芯片技术检测标记染色体  

Detection of small supernumerary marker chromosome by single nucleotide polymorphism microarray chips

作　　者：闻小慧[1] 戚红[1] 任捷[1] 杨锴[1] 祝建疆[1] 陈佳靓[1] 蔡莉蓉[1] 曾雯[1] 

机构地区：[1]北京市海淀区妇幼保健院遗传科,100080

出　　处：《中华儿科杂志》2015年第3期198-202,共5页Chinese Journal of Pediatrics

摘　　要：目的 应用单核苷酸多态性芯片技术进行新生儿标记染色体检测.方法 选取2013年1月至2014年1月在北京市海淀区妇幼保健院出生的、其母亲在孕期检查时提示胎儿超声异常的新生儿,经家属知情同意,留取其脐血,行G显带染色体核型分析;其中2例新生儿存在微小额外标记染色体（例1核型为嵌合体mos 47,XY,＋mar[45]/46,XY[5],例2核型为mos 47,XY,＋mar[30]/46,XY[20],常规显带技术无法明确其区带和来源,因而用同期采集的脐带血提取DNA,行单核苷酸多态性芯片分析.结果 例1的微小额外标记染色体来源于8号染色体,大小约为78.6 Mb,文献报道该区域可导致8p22重复综合征;例2的微小额外标记染色体来源于13号染色体,约32.7 Mb的重复,未见相关致病性拷贝数变异（CNVs）报道.例1出生后随访胼胝体发育不全,右眼睑明显下垂,上下肢肌张力低,智力发育落后同龄儿,例2出生后随访智力体格发育未见异常.结论 单核苷酸多态性芯片技术能够在DNA水平上甄别新生儿新发微小额外标记染色体的来源,但其致病性有待进一步的随访验证,不失为传统染色体核型分析的重要补充.Objective To apply single nucleotide polymorphism （SNP） microarray for delineation of small supernumerary marker chromosome （sSMC） in two newborns.Method Chromosome karyotyping was performed on newborns who were born in Jan.2013 and Jan.2014 in Haidian Maternal and Child Health Hospital because of the abnormalities found in pregnancy checkups.SNP microarray analysis was carried out on 2 newborns with de novo sSMCs （one was mos 47,XY,＋ mar[45]/46,XY[5],and the other was mos 47,XY,＋ mar [30]/46,XY [20]）,which could not be determined by conventional banding techniques.Genomic DNA was extracted from cord blood samples,amplified,tagged and hybridized following the manufacturer＆#39;s protocol.Data were collected and analyzed.Result There was a 78.6 Mb duplication in chromosome 8 for Newborn A,which was associated with 8p22 duplication syndrome; and a 32.7 Mb duplication in chromosome 13 for Newborn B,which was not yet reported definitely as pathogenic.The newborn A was identified with agenesis of the corpus callosum,obvious right eyelid drooping,the onset of low muscle tone and mental developmental lag behind their peers,while the newborn B had normal findings on physical and mental evaluation.Conclusion SNP-array can identify sSMCs of newborns at the DNA level,and can be used as an important supplement to the conventional karyotype analysis,but the pathogenicity of positive outputs need further verification.

关 键 词：染色体 多态性 单核苷酸 散在重复序列 

分 类 号：R440[医药卫生—诊断学]