Genomic DNA obtained from a five-year-old girl with hearing loss was analyzed via the hearing loss-targeted gene panels. We identified the compound heterozygous variants c.8559-2A>G and c.4749delT in Usher syndrome type 2A (USH2A) gene as the underlying cause of the patient; the former variation has been reported in the literature, but not the latter. The parents of the girl were heterozygous carriers. The two variants were classified as pathogenic. Based on these findings, amniotic fluid samples were used for prenatal diagnosis of the couple\'s fetus, which was found to carry c.4749delT but not c.8559-2A>G variation. During the follow-up period of more than 9 months after the birth of the fetus, it was confirmed that the infant was healthy.
The results of the present study identified two compound heterozygous USH2A variants in a patient with hearing loss and reported a novel USH2A variant which expands the spectrum of USH2A variants in USH.
通过针对听力损失的基因面板分析了从一名5岁听力损失女孩获得的基因组DNA。我们确定了Usher综合征2A(USH2A)基因中的复合杂合变体c.8559-2A>G和c.4749delT是患者的根本原因;文献中已经报道了前者的变异,但不是后者。女孩的父母是杂合携带者。这两种变体被分类为致病性的。基于这些发现,羊水样本用于这对夫妇的胎儿的产前诊断,发现携带c.4749delT,但不携带c.8559-2A>G变异。在胎儿出生后9个月以上的随访期内,证实婴儿是健康的。
本研究的结果在患有听力损失的患者中鉴定了两种复合杂合USH2A变体,并且报道了一种新的USH2A变体,其扩展了USH中的USH2A变体的谱。