Tekin M, Duman T, Boğoçlu G, Incesulu A, Cin S, Akar N
Division of Pediatric Molecular Pathology and Genetics, Ankara University School of Medicine, Ankara 06 100, Turkey.
Genet Couns. 2003;14(4):379-86.
Mutations in the GJB2 (connexin 26-Cx26) gene are responsible for 20-50% of cases with prelingual non-syndromic deafness in a large part of the world including Turkey. Although most of the cases with Cx26 deafness have a recessive mode of inheritance, a small group of families demonstrated dominant or pseudodominant inheritance. In this report we present a Turkish family in which the proband had congenital profound deafness and was found to be homozygous for the 35delG mutation, whereas the father and a paternal uncle who had milder, late-onset sensorineural hearing loss had compound heterozygous 35delG and L90P mutations. This family and previous reports with the L90P mutation demonstrate that the hearing loss associated with the L90P/35delG genotype is consistently milder than that of 35delG homozygotes. GJB2 gene screening should be considered in families with seemingly dominant inheritance and late-onset moderate hearing loss.
在包括土耳其在内的世界大部分地区，GJB2（连接蛋白26 - Cx26）基因突变导致20%至50%的语前非综合征性耳聋病例。尽管大多数Cx26耳聋病例具有隐性遗传模式，但一小部分家庭表现出显性或假显性遗传。在本报告中，我们介绍了一个土耳其家庭，该家庭的先证者患有先天性重度耳聋，被发现为35delG突变的纯合子，而患有轻度迟发性感音神经性听力损失的父亲和一位叔祖父则为35delG和L90P突变的复合杂合子。这个家庭以及之前有关L90P突变的报告表明，与L90P/35delG基因型相关的听力损失始终比35delG纯合子的听力损失轻。对于具有看似显性遗传和迟发性中度听力损失的家庭，应考虑进行GJB2基因筛查。
