营养不良性大疱性表皮松解症COL7A1基因诊断及产前诊断  

COL7A1 gene mutation analysis of dystrophic epidermolysis bullosa and prenatal diagnosis

作　　者：刘宁[1] 郭宏湘[2] 孔祥东[1] 史惠蓉[3] 杨昀 吴庆华[1] 赵振华[1] 江淼[1] 

机构地区：[1]郑州大学第一附属医院产前诊断中心,450052 [2]郑州大学第一附属医院儿科,450052 [3]郑州大学第一附属医院妇产科,450052 [4]武汉华大医学检验所

出　　处：《中华医学杂志》2015年第4期277-282,共6页National Medical Journal of China

摘　　要：目的 分析2个营养不良性大疱性表皮松解症（DEB）家系致病基因COL7A1基因突变位点,并在此基础上探讨COL7A1基因分析用于产前诊断的可行性.方法 应用全基因捕获新一代测序（NGS）对2013年10月和2014年4月在郑州大学第一附属医院就诊的2个DEB家系中2例先证者COL7A1基因进行全基因突变检测,获得变异序列后,针对所检出变异序列进行PCR扩增后Sanger双向测序对2个DEB家系中2例先证者及其父母和100名健康个体的COL7A1基因序列进行突变验证分析,确定致病突变后,对其中1个家系中的高危胎儿进行孕早期产前诊断.结果 共发现4种COL7A1基因突变：c.5230G ＞T （p.E1744X）、c.5932C ＞T （p.R1978X）、c.5605-10 T＞G（IVS66-10 T＞G）、c.8305-1G＞A（IVS110-1G＞A）.其中p.E1744X、IVS66-10 T＞G和IVS110-1G＞A为国际首次报道的突变.家系1中先证者携带COL7A1基因p.E1744X和p.R1978X无义突变,父母分别为杂合突变携带者;家系2中先证者携带COL7A1基因IVS66-10T＞G和IVS110-1G ＞A剪接区突变,父母分别为杂合突变携带者;100名健康个体未检测到上述突变.家系1中产前诊断胎儿携带与其先证者相同的突变为受累胎儿,胎儿父母选择治疗性引产术后,取胎儿标本行基因诊断,结果与产前诊断相同.结论 COL7A1基因突变是该2个DEB家系的致病原因,NGS结合Sanger测序方法可以快速且准确地进行该病的基因诊断和产前诊断.Objective To analyze the mutations of COL7A1 gene in two dystrophic epidermolysis bullosa （DEB） pedigrees and make prenatal diagnosis for high-risk 1 1-week-old fetuses.Methods COL7A1 gene was first analyzed by next-generation sequencing for detecting suspicious gene mutations of two probands.And then the mutations were confirmed by polymerase chain reaction and Sanger sequencing in probands,parents and unrelated healthy individuals.Prenatal genetic diagnosis for high-risk fetus was performed by chorionic villus sampling after genotyping.Results Four mutations were detected in 2 pedigrees：c.5230G 〉 T （p.E1744X）,c.5932C 〉 T （p.R1978X）,c.5605-10 T 〉 G（IVS66-10 T 〉 G）,c.8305-1G 〉 A（IVS110-1G 〉 A） among which p.E1744X,IVS66-10 T 〉 G and IVS110-1G 〉 A mutations were first reported.The proband in No.1 family carried p.E1744X and p.R1978X nonsense mutations and her parents were carriers.The proband in No.2 family carried IVS66-10 T 〉 G and IVS110-1G 〉 A splicing mutations and her parents were carriers.All four mutations were not found in 100 healthy individuals.Prenatal diagnosis in No.1 family indicated that the fetus also carried p.E1744X and p.R1978X nonsense mutations as the proband.The fetal parents decided to terminate pregnancy and the result of gene analysis for aborted tissue was consistent with that of prenatal diagnosis.Conclusions COL7A1 gene mutation is etiological for two DEB families.Next-generation sequencing plus Sanger sequencing is effective and accurate for making gene diagnosis and prenatal diagnosis.

关 键 词：表皮松解 大疱性 营养不良性 产前诊断 新一代测序 Sanger测序 COL7A1基因 

分 类 号：R714.5[医药卫生—妇产科学]