Li Yunlong, Zhu Baosheng
Medical Faculty, Affiliated Hospital of Kunming University of Science and Technology (The First People's Hospital of Yunnan Province), Kunming University of Science and Technology, Kunming, Yunan 650500, P.R. China.
Mol Med Rep. 2016 Jul;14(1):319-24. doi: 10.3892/mmr.2016.5280. Epub 2016 May 13.
Mutations in the SLC26A4 gene have been shown to cause a type of deafness referred to as large vestibular aqueduct syndrome (LVAS), whereas mutations in the GJB3 gene have been associated with nonsyndromic deafness. However, the clinical phenotypes of these mutations vary and remain to be fully elucidated. The present study performed genetic analysis of a Chinese family, in which the child was deaf and the parents were healthy. Sanger sequencing demonstrated that the affected individual harbored three heterogeneous mutations in the SLC26A4 and GJB3 genes, as follows: SLC26A4 IVS-2 A>G, SLC26A4 c.2168 A>G and GJB3 c.538 C>T. The affected individual exhibited hearing loss and was diagnosed with LVAS by computed tomography scan. The mother and father of the affected individual harbored the heterogeneous mutations of SLC26A4 IVS-2 A>G and GJB3 c.538 C>T, and the heterozygous mutation of SLC26A4 c.2168 A>G, respectively. Neither parents exhibited any hearing loss. The results obtained from the deaf patient provided genetic and clinical evidence that carrying combined heterogeneous mutations in the GJB3 and SLC26A4 genes may be involved in the etiology of severe hearing loss, of which the mechanism requires further examination.
已证实SLC26A4基因突变会导致一种被称为大前庭导水管综合征（LVAS）的耳聋类型，而GJB3基因突变与非综合征性耳聋有关。然而，这些突变的临床表型各不相同，仍有待充分阐明。本研究对一个中国家庭进行了基因分析，该家庭中孩子耳聋而父母健康。桑格测序表明，受影响个体在SLC26A4和GJB3基因中存在三个异质性突变，如下：SLC26A4基因IVS-2 A>G、SLC26A4基因c.2168 A>G和GJB3基因c.538 C>T。受影响个体表现出听力损失，并通过计算机断层扫描被诊断为大前庭导水管综合征。受影响个体的母亲和父亲分别携带SLC26A4基因IVS-2 A>G和GJB3基因c.538 C>T的异质性突变，以及SLC26A4基因c.2168 A>G的杂合突变。父母双方均未表现出任何听力损失。从该耳聋患者获得的结果提供了遗传和临床证据，表明携带GJB3和SLC26A4基因的联合异质性突变可能与严重听力损失的病因有关，其机制需要进一步研究。
