He Xiang, Gu Feng, Wang Ze, Wang Chong, Tong Yi, Wang Yujing, Yang Juhua, Liu Wei, Zhang Meng, Ma Xu
Department of Genetics, National Research Institute for Family Planning, Beijing, China.
Genet Test. 2008 Dec;12(4):607-13. doi: 10.1089/gte.2008.0070.
Idiopathic congenital nystagmus (ICN) is a common oculomotor disorder characterized by bilateral involuntary, periodic, and predominantly ocular oscillations. X-linked ICN (XLICN) with incomplete penetrance in females is the most common inheritance form, and FERM domain containing (FRMD7) mutation is the major reason for XLICN families. To date, 39 FRMD7 mutations have been identified, and 50% of the XLICN pedigrees have yielded FRMD7 mutations in the Western population. In this study, we identified a novel frameshift mutation (c.1274-1275delTG) in the FRMD7 gene in six XLICN pedigrees. Incorporated with data reported from other two Chinese groups, approximately 47% XLICN pedigrees were caused by the FRMD7 mutation in China. Therefore, this study showed that mutation analysis of the FRMD7 gene had diagnostic value not only in the Western population but also in one of the biggest Eastern populations, Chinese XLICN families. In addition, the results indicated the type of FRMD7 mutation associated with the penetrance of female carriers of XLICN.
特发性先天性眼球震颤（ICN）是一种常见的眼球运动障碍，其特征为双侧不自主、周期性且主要为眼部的振荡。女性具有不完全外显率的X连锁ICN（XLICN）是最常见的遗传形式，含FERM结构域蛋白7（FRMD7）突变是XLICN家族的主要病因。迄今为止，已鉴定出39种FRMD7突变，在西方人群中，50%的XLICN家系存在FRMD7突变。在本研究中，我们在6个XLICN家系中鉴定出FRMD7基因的一种新型移码突变（c.1274-1275delTG）。结合其他两个中国研究组报告的数据，在中国约47%的XLICN家系由FRMD7突变引起。因此，本研究表明，FRMD7基因突变分析不仅在西方人群中具有诊断价值，在最大的东方人群之一——中国XLICN家系中也具有诊断价值。此外，结果表明了与XLICN女性携带者外显率相关的FRMD7突变类型。
