G6PD缺乏症合并Turner综合征嵌合体的遗传学分析

Genetic analysis of G6PD deficiency with Turner syndrome mosaicism

目的探讨1例疑似G6PD缺乏症合并Turner综合征嵌合体先证者的相关遗传学病因。方法采用多色探针荧光PCR熔解曲线法和Sanger测序法对G6PD酶活性降低的先证者及家系进行G6PD基因诊断,联合染色体核型分析和QF-PCR分析等多种方法对本例G6PD缺乏症的家系进行分析。结果先证者父亲为G6PD基因c.1388G>A纯合突变;母亲G6PD基因未检测出12种常见突变;先证者染色体核型为45,X[67]/46,XX[33],G6PD基因c.1388G>A杂合突变(测序的野生位点峰与突变位点峰面积比约为1∶2),G6PD基因突变遗传自父亲。结论对于G6PD酶活性异常或基因检测发现异常结果无法对该结果进行解释时,应同时考虑是否存在染色体病,并结合临床表型、实验室检查结果及家系分析,做出全面的诊断,达到准确诊断及正确的遗传咨询。

Objective To explore the genetic etiology of a suspected proband of G6 PD deficiency and Turner syndrome chimera. Methods G6 PD gene of proband and families was diagnosed by multicolor probe fluorescent PCR melting curve gene mutation detection and Sanger sequencing technology. The pedigree of G6 PD deficiency and chromosomal disease were analyzed by peripheral blood karyotype analysis and QF-PCR technology. Results The father had a homozygous mutation in G6 PD gene c.1388 G>A. The G6 PD gene of mother wasn’t detected 12 kinds of common mutation. The proband had a heterozygous mutation in G6 PD gene c.1388 G>A(the area ratio of wild site peak to mutant site peak sequenced was about 1 : 2)with chimera of Turner syndrome(45,X[67]/46,XX[33]). It was inferred that the G6 PD gene defect of the proband was inherited from the father. Conclusion In case of abnormal G6 PD enzyme activity or abnormal gene detecting, the existence of chromosome disease should be considered at the same time. Meanwhile, clinical phenotype, family analysis and laboratory test results should be combined to make an accurate diagnosis and achieve early detection and early intervention.