1例Bartter综合征的家系基因突变分析和产前诊断

Gene mutation analysis and prenatal diagnosis of a family with Bartter syndrome

摘要:

目的 对1例Bartter综合征的家系进行相关致病基因突变分析和产前诊断。方法 应用高通量捕获测序技术、PCR-Sanger测序法从基因组水平对先证者进行Bartter综合征相关致病基因的检测及家系分析；明确遗传学病因后进一步对已妊娠5个月的先证者母亲抽取羊水进行产前诊断。结果 先证者编码氯通道蛋白CLC-Kb的CLCNKB基因存在c.88C > T （p.Arg30*） 和c.968+2T > A复合杂合突变，其中c.88C > T （p.Arg30*） 为已报道的致病突变，c.968+2T > A为新突变。家系分析显示这两个突变分别源自其母亲和父亲。产前诊断结果显示胎儿未遗传其父母的突变，为两个位点均正常的健康个体，随诊显示出生的婴儿健康，证实了基因诊断及产前诊断的准确性。结论 CLCNKB基因的复合杂合突变c.88C > T （p.Arg30*） 和c.968+2T > A为先证者的病因，产前诊断可以预防该家系Bartter综合征的再发风险。

Abstract:

Objective To investigate the mutation of related genes and prenatal diagnosis of a family with Bartter syndrome (BS). Methods The high-throughput capture sequencing technique and PCR-Sanger sequencing were used to detect pathogenic genes in the proband of this family and analyze the whole family at the genomic level. After the genetic cause was clarified, the amniotic fluid was collected from the proband's mother who was pregnant for 5 months for prenatal diagnosis. Results The proband carried compound heterozygous mutations of c.88C > T (p.Arg30*) and c.968+2T > A in the CLCNKB gene; c.88C>T (p.Arg30*) had been reported as a pathogenic mutation, and c.968+2T > A was a new mutation. Pedigree analysis showed that the two mutations were inherited from the mother and father, respectively. Prenatal diagnosis showed that the fetus did not inherit the mutations from parents and had no mutations at the two loci. The follow-up visit confirmed that the infant was in a healthy state, which proved the accuracy of genetic diagnosis and prenatal diagnosis. Conclusions The compound heterozygous mutations c.88C>T (p.Arg30*) and c.968+2 T> A in the CLCNKB gene are the cause of BS in the proband, and prenatal diagnosis can prevent the risk of recurrence of BS in this family.