三个手足裂畸形家系的遗传学研究  

Genetic analysis of three families affected with split-hand/split-foot malformation

作　　者：何文斌[1,2] 林戈[1,2] 梁平 程德华[1,2] 胡晓[1] 周立花[1] 熊波 谭跃球[1,2] 卢光琇[1,2] 李汶[1,2] 

机构地区：[1]中南大学生殖与干细胞工程研究所,长沙410078 [2]中信湘雅生殖与遗传专科医院,长沙410078 [3]加拿大布鲁克大学,圣凯瑟琳市L2S3A1

出　　处：《中华医学遗传学杂志》2017年第4期476-480,共5页Chinese Journal of Medical Genetics

基　　金：国家重点研发计划（2016YFC1000206）

摘　　要：目的对3个指（趾）骨异常家系进行遗传性致病原因分析，为该3个家系进行遗传咨询和生育指导提供理论依据。方法采集家系1中21人、家系2中2人、家系3中2人的外周血，提取外周血DNA、家系1制作外周血染色体中期分裂相。应用PCR-测序、全基因组芯片、荧光原位杂交、实时荧光定量PCR和高通量测序等技术对3家系成员进行基因突变分析，并初步探讨检测到的突变对指（趾）骨发育的影响。结果（1）全基因组芯片和实时荧光定量PCR结果提示家系1中的患者FKSG40、TLX1、LBX1、BTRC、POLL和部分FBXW4基因（第6～9外显子）存在杂合重复，家系3中的患者LBX1、BTRC、POLL和部分FBxw4基因（第6～9外显子）存在杂合重复。（2）PCR-测序分析发现家系2患者的TP63基因均存在C．692A〉G（P．Tyr231Cys）杂合突变。（3）根据荧光原位杂交结果，家系1中Ⅲ13患者的杂交信号均位于10号染色体长臂，且在其他染色体区域未见特异性杂交信号，提示可能为原位重复。（4）对家系1患者10q24区域显微切割后行高通量测序未检测到断裂连接点。结论确诊了3个指（趾）骨异常家系的遗传性致病原因，为家系的遗传咨询和产前诊断（胚胎植入前遗传学诊断）提供了依据。Objective To explore the genetic etiology of three families affected with split-hand/split- foot malformation （SHFM）. Methods Peripheral venous blood samples from 21 members of pedigree 1,2 members of pedigree 2, and 2 members of pedigree 3 were collected. PCR-Sanger sequencing, microarray chip,fluorescence in situ hybridization （FISH）, real-time PCR, and next-generation sequencing were employed to screen the mutations in the 3 families. The effect of the identified mutations on the finger （toe） abnormality were also explored. Results Microarray and real-time PCR analysis has identified a duplication in all patients from pedigrees 1 and 3, which have spanned FKSG40, TLX1, LBX1, BTRC, POLL and FBXW4 （exons 6-9） and LBX1, BTRC, POLL and FBXW4 （exons 6-9） genes,respectively. A missense mutation of the TP63 gene,namely c. 692A〉G （p. Tyr231Cys）, was found in two patients from pedigree 2. FISH analysis of chromosome 10 showed that the rearrangement could fita tandem duplication model. However, next-generation sequencing did not identify the breakpoint. Conclusion The genetic etiology for three families affected with SHFM have been identified,which has provideda basis for genetic counseling and guidance for reproduction.

关 键 词：手足裂畸形 染色体10q24区域 微重复 TP63基因 

分 类 号：R440[医药卫生—诊断学] R682[医药卫生—临床医学]