Lin Hui, Wang Li, Zhou Nan, Su Hong, Gu Jingzhi, Qi Yanhua
Department of Ophthalmology, the Second Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang, People's Republic of China.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi. 2008 Feb;25(1):6-10.
To map the disease locus for a congenital cataract family, and detect the disease-causing gene.
An autosomal dominant congenital cataract family was genotyped by genome wide scan using 382 autosomal microsatellite markers from ABI-MD10. Two-point linkage analysis was carried out by the MLINK program.
The disease locus of this family was mapped at 12p11.2-q15. Sequence analysis of a candidate gene-major intrinsic protein (MIP) revealed a novel missense mutation G-->A at the nucleotide 702 in exon 4, which resulted in a substitution of arginine to lysine at codon 233 (p.R233K).
The mutation G-->A at nt702 in MIP gene was associated with the binocular polymorphic congenital cataract in the family. This transition occurring at the C-terminus of MIP might decrease the stability of the C-end of the protein and impact the function of the protein.
定位一个先天性白内障家系的疾病位点，并检测致病基因。
利用来自ABI-MD10的382个常染色体微卫星标记，通过全基因组扫描对一个常染色体显性先天性白内障家系进行基因分型。采用MLINK程序进行两点连锁分析。
该家系的疾病位点定位于12p11.2-q15。对候选基因主要内在蛋白（MIP）进行序列分析，发现在外显子4的核苷酸702处有一个新的错义突变G→A，导致密码子233处的精氨酸被赖氨酸取代（p.R233K）。
MIP基因第702位核苷酸的G→A突变与该家系的双眼多形性先天性白内障相关。此突变发生在MIP的C末端，可能会降低蛋白质C末端的稳定性并影响其功能。
