一个与中国人先天性核性和后极性白内障相关的 γD-晶体蛋白的无意义突变。

A nonsense mutation of γD-crystallin associated with congenital nuclear and posterior polar cataract in a Chinese family.

机构信息

1. Eye Center, Second Affiliated Hospital of Medical College, Zhejiang University, Hangzhou, Zhejiang, China ; 2. Key Laboratory of Ophthalmology of Zhejiang Province, China.

3. Center for Structural Biology and Department of Chemistry and the Institute for Chemical Biology, Vanderbilt University Medical Center, USA.

出版信息

Int J Med Sci. 2014 Jan 5;11(2):158-63. doi: 10.7150/ijms.7567. eCollection 2014.

OBJECTIVE

The goal of this study was to characterize the disease-causing mutations in a Chinese family with congenital nuclear and posterior polar cataracts.

METHODS

Clinical data of patients in the family were recorded using slit-lamp photography and high definition video. Genomic DNA samples were extracted from the peripheral blood of the pedigree members and 100 healthy controls. Mutation screening was performed in the candidate genes by bi-directional sequencing of the amplified products.

RESULTS

The congenital cataract phenotype of the pedigree was identified by slit-lamp examinations and observation during surgery as nuclear and posterior polar cataracts. Through the sequencing of the candidate genes, a heterozygous c. 418C>T change was detected in the coding region of the γD-crystallin gene (CRYGD). As a result of this change, a highly conserved arginine residue was replaced by a stop codon (p. R140X). This change was discovered among all of the affected individuals with cataracts, but not among the unaffected family members or the 100 ethnically matched controls.

CONCLUSIONS

This study identified a novel congenital nuclear and posterior polar cataract phenotype caused by the recurrent mutation p. R140X in CRYGD.

目的

本研究旨在分析一个中国先天性核性和后极性白内障家系的致病突变。

方法

通过裂隙灯摄影和高清录像记录家系成员的临床资料。采集家系成员及 100 名健康对照者外周血基因组 DNA 样本，采用扩增产物双向测序的方法对候选基因进行突变筛查。

结果

通过裂隙灯检查和手术观察，该家系的先天性白内障表型被确定为核性和后极性白内障。通过对候选基因的测序，在 γD-晶体蛋白（CRYGD）的编码区发现了一个杂合的 c.418C>T 变化。由于这种变化，一个高度保守的精氨酸残基被终止密码子（p.R140X）取代。这一变化在所有白内障患者中均有发现，但在未受影响的家庭成员或 100 名种族匹配的对照者中未发现。