Waardenburg综合征(Waardenburg syndrome,WS)是一种常染色体显形遗传疾病,以毛发、皮肤、眼睛色素异常以及感音神经性听力障碍为特征.本文报告1例8月龄男患儿,表现为先天性耳聋伴双侧虹膜灰蓝色、毛发颜色偏黄、内眦外移.患儿及其家系成员均进行基因测序分析.基因检测结果表明患儿存在MITF基因的c.970_972del(p.R324del)杂合变异,为新生变异;患儿父母该位点均无变异.根据美国医学遗传学与基因组学学会(American College of Medical Genetics and Genomics,ACMG)指南判读该变异为致病变异.MITF基因c.970_972del(p.R324del)在WS2A型中为一新发突变位点,是导致该患儿患病的致病基因.
MITF gene mutation in a family with Waardenburg syndrome type 2A
Waardenburg syndrome(WS)is an autosomal dominant genetic disorder characterized by abnormalities in hair,skin,eye pigmentation,and sensorineural hearing loss.This article reports a case of an 8-month-old male child with congenital deafness accompanied by bilateral grey-blue irises,yellowish hair color,and lateral displacement of the inner eye corners.The child and his family members underwent genetic sequencing analysis.The genetic testing results indicated a heterozygous mutation of c.970_972del(p.R324del)in the MITF gene in the child,which is a de novo mutation.Neither of the parents had a mutation at the same site.According to the American College of Medical Genetics and Genomics(ACMG)guidelines,this mutation was interpreted as a pathogenic variant.The MITF gene c.970_972del(p.R324del)represents a new mutation site in WS Type 2A and is the pathogenic gene causing the disease in this child.
Waardenburg syndrome Type 2AMITF genehearing lossmutation