一例指甲-髌骨综合征的产前诊断及家系分析

Prenatal diagnosis and pedigree analysis of a case of Nail-patella syndrome

目的探讨1例指甲-髌骨综合征的产前诊断及其家系的遗传分析。方法结合临床表型、影像学表现以及全外显子组测序(whole exome sequencing,WES)对患病家系进行基因检测和产前诊断。结果羊水WES分析发现胎儿LMX1B基因存在c.139+1G>T剪接位点杂合变异[Chr9(GRCh37):g.129376868G>T],经Sanger验证结果一致。孕妇、其大女儿以及其母亲测序发现携带相同的杂合变异,其丈夫该位点未见异常。检索HGMD数据库提示c.139+1G>T为既往未报道的变异。结论指甲-髌骨综合征是临床表现差异较大的显性遗传病,WES有助于其基因分析与产前诊断。

Objective To carried out prenatal diagnosis and genetic analysis for a case with Nail-patella syndrome.Methods Based on the clinical phenotype and prenatal imaging,genetic testing and prenatal diagnosis were carried out through whole exome sequencing(WES)and Sanger sequencing.Results Analysis of amniotic fluid showed that the fetus has carried a heterozygous c.139+1G>T splicing site variant[Chr9(GRCh37):g.129376868G>T]of the LMX1B gene,which was verified by Sanger sequencing.The same heterozygous variant was found in the pregnant woman,her daughter and her mother but not in her husband.Searching of HGMD database showed that the c.139+1G>T was previously unreported.Conclusion Nail-patella syndrome is an autosomal dominant genetic disorder with various clinical manifestations.WES is helpful for its genetic and prenatal diagnosis.