Yang Guoxing, Xing Baogang, Liu Guangcai, Lu Xiangqing, Jia Xingang, Lu Xiangqing, Wang Xiuli, Yu Hongyan, Fu Yanjiang, Zhao Jialiang
Department of Opthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
Mol Vis. 2011 Apr 27;17:1070-3.
Congenital cataract is both a clinically and genetically heterogeneous lens disorder. The purpose of this study is to map and identify the mutation in an autosomal dominant congenital nuclear cataract in a Chinese family.
Patients were given physical examinations and their blood samples were collected for DNA extraction. Genotyping was performed by microsatellite markers and logarithm of odds (LOD) scores were calculated using the LINKAGE programs. Mutation detection was performed by direct sequencing.
Linkage to the gap-junction protein α3 (GJA3) locus was verified. Sequencing of GJA3 revealed a G>A transition at nucleotide position c.139, which causes an Asn substitution for the conservative Asp at codon 47 (P.D47N).This mutation is identified in all affected individuals but is not found in 100 control chromosomes.
Our results identify that the mutation (D47N) in GJA3 is responsible for this Chinese pedigree. It is further identified that GJA3 is responsible for congenital cataract. In our study, the novel mutation broadens the spectrum of GJA3 mutations.
先天性白内障是一种在临床和遗传上均具有异质性的晶状体疾病。本研究旨在定位并鉴定一个中国家系中常染色体显性遗传先天性核性白内障的突变。
对患者进行体格检查，并采集血样用于DNA提取。通过微卫星标记进行基因分型，并使用LINKAGE程序计算优势对数（LOD）分数。通过直接测序进行突变检测。
证实与缝隙连接蛋白α3（GJA3）基因座连锁。GJA3测序显示核苷酸位置c.139处发生G>A转换，导致第47密码子处保守的天冬氨酸被天冬酰胺取代（P.D47N）。在所有患病个体中均鉴定出该突变，但在100条对照染色体中未发现。
我们的结果表明，GJA3中的突变（D47N）是这个中国家系先天性白内障的致病原因。进一步确定GJA3与先天性白内障有关。在我们的研究中，该新突变拓宽了GJA3突变谱。
