Wang Honghan, Wang Xinwei, He Chufeng, Li Haibo, Qing Jie, Grati Mhamed, Hu Zhengmao, Li Jiada, Hu Yiqiao, Xia Kun, Mei Lingyun, Wang Xingwei, Yu Jianjun, Chen Hongsheng, Jiang Lu, Liu Yalan, Men Meichao, Zhang Hailin, Guan Liping, Xiao Jingjing, Zhang Jianguo, Liu Xuezhong, Feng Yong
Department of Otolaryngology, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, Hunan, China.
Department of Head and Neck Surgery, Hunan Provincial Tumor Hospital and the Affiliated Tumor Hospital of Xiangya Medical School, Central South University, Changsha, Hunan, China.
J Hum Genet. 2015 Mar;60(3):119-126. doi: 10.1038/jhg.2014.114. Epub 2015 Jan 15.
Autosomal dominant nonsyndromic hearing loss (ADNSHL/DFNA) is a highly genetically heterogeneous disorder. Hitherto only about 30 ADNSHL-causing genes have been identified and many unknown genes remain to be discovered. In this research, genome-wide linkage analysis mapped the disease locus to a 4.3 Mb region on chromosome 19q13 in SY-026, a five-generation nonconsanguineous Chinese family affected by late-onset and progressive ADNSHL. This linkage region showed partial overlap with the previously reported DFNA4. Simultaneously, probands were analyzed using exome capture followed by next-generation sequencing. Encouragingly, a heterozygous missense mutation, c.505G>A (p.G169R) in exon 3 of the CEACAM16 gene (carcinoembryonic antigen-related cell adhesion molecule 16), was identified via this combined strategy. Sanger sequencing verified that the mutation co-segregated with hearing loss in the family and that it was not present in 200 unrelated control subjects with matched ancestry. This is the second report in the literature of a family with ADNSHL caused by CEACAM16 mutation. Immunofluorescence staining and western blots also prove CEACAM16 to be a secreted protein. Furthermore, our studies in transfected HEK293T cells show that the secretion efficacy of the mutant CEACAM16 is much lower than that of the wild type, suggesting a deleterious effect of the sequence variant.
常染色体显性非综合征性听力损失(ADNSHL/DFNA)是一种高度遗传异质性疾病。迄今为止,仅鉴定出约30个导致ADNSHL的基因,许多未知基因仍有待发现。在本研究中,全基因组连锁分析将疾病位点定位到SY-026这个五代非近亲中国家系的19号染色体q13上的一个4.3 Mb区域,该家系受迟发性和进行性ADNSHL影响。这个连锁区域与先前报道的DFNA4有部分重叠。同时,对先证者进行外显子捕获后接着进行二代测序分析。令人鼓舞的是,通过这种联合策略在癌胚抗原相关细胞黏附分子16(CEACAM16)基因的第3外显子中鉴定出一个杂合错义突变,即c.505G>A(p.G169R)。桑格测序证实该突变与家族中的听力损失共分离,并且在200名具有匹配血统的无关对照受试者中不存在。这是文献中关于由CEACAM16突变导致ADNSHL的家系的第二篇报道。免疫荧光染色和蛋白质印迹也证明CEACAM16是一种分泌蛋白。此外,我们在转染的HEK293T细胞中的研究表明,突变型CEACAM16的分泌效率远低于野生型,提示该序列变异具有有害作用。