非综合征性耳聋(nonsyndromic hearing impairment, NSHI)是一种十分常见的人类神经系统疾病, 约有1/1000的新生儿患有语前聋。GJB2基因编码间隙连接蛋白Cx26, 是最常见的NSHI致病基因, 大约50%的常染色体隐性遗传NSHI是由GJB2基因突变引起的。在本研究中, 收集了江苏省一个复杂的非综合征性耳聋家系, 并对其进行了分子遗传学研究。对所有已知常染色体隐性遗传的NSHI致病基因, 选用其侧翼的微卫星标记进行连锁分析, 发现该家系的致病基因与D13S175连锁。对GJB2基因进行整个编码区域的测序, 发现235碱基处发生了碱基C的纯合缺失, 这一突变可能是该家系中绝大多数患者致病的遗传基础。

Nonsyndromic neurosensory hearing impairment (NSHI) is the most common human sensory disorder. Approximately one in a thousand children is born with prelingual hearing loss. Mutations of the GJB2 gene, which encodes Connexin 26, are the most common cause of hereditary NSHI in many ethnic populations, and are responsible for 50% of cases of autosomal recessive NSHI. In this study, we recruited a complex NSHI pedigree from Jiangsu province of China. Linkage analysis of microsatellite markers flanking all known arNSHI genes linked the causative gene in the family to the polymorphic macrosatellite marker D13S175. Direct DNA sequencing of the whole coding region of GJB2 revealed that a common homozygous mutation 235delC was responsible for most of the affected members in the NSHI family.