Mutations in the GJB2 gene are a main cause of autosomal‐recessive nonsyndromic hearing loss (ARNSHL) in many populations. Previous studies have estimated the average frequency of GJB2 mutations to be ∼16% in Iran, but would vary among different ethnic groups. Here, we have taken together and reviewed results from our two previous publications and data from searching other published mutation reports to provide a comprehensive collection of data for GJB2 mutations and HL in central Iran. In all, 332 unrelated families were included and analyzed for the prevalence and type of the GJB2 gene mutations. In total, the frequency of GJB2 mutations was found to be 16% in the central provinces, which is significantly higher than those identified in southern populations of Iran. Also, c.35delG was the most frequent mutation in the related population. The present study suggests that mutations in the GJB2 gene, especially c.35delG, are important causes of HL in central Iran and can be used as a basis of genetic counseling and clinical guidelines in this region.

中文翻译：

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伊朗中部与 GJB2 相关的听力损失：基因突变的频谱和频率回顾

GJB2 基因突变是许多人群中常染色体隐性非综合征性听力损失 (ARNSHL) 的主要原因。先前的研究估计 GJB2 突变的平均频率在伊朗约为 16%，但会因种族而异。在这里，我们汇总并审查了我们之前两篇出版物的结果以及搜索其他已发表突变报告的数据，以提供伊朗中部 GJB2 突变和 HL 的全面数据集合。总共包括了 332 个不相关的家庭，并分析了 GJB2 基因突变的流行率和类型。总的来说，中部省份的 GJB2 突变频率为 16%，明显高于伊朗南部人群的突变频率。此外，c.35delG 是相关人群中最常见的突变。