先天性白内障一家系的致病基因初步筛查

目的：对常染色体显性遗传先天性白内障一家系的致病基因进行初步筛查。方法收集常染色显性遗传的白内障一家系23名成员的外周静脉血，提取基因组DNA，选取与已知常染色体显性遗传的先天性白内障的候选基因CRYGD、GJA3，采用软件Linkage对该家系2个基因附近共10个STR位点进行两点法连锁分析，筛查这2个基因是否为此家系的致病基因。结果对该家系的基因连锁分析表明，基因CRYGD、JGA3所有编码区及外显子与内含子交界处均未发现基因序列的突变。结论基因CRYGD、GJA3不是该家系的遗传致病基因，对该家系需进一步做全基因组扫描，以发现致病基因在染色体上的可疑区间。

Linkage analysis of one Chinese family with autosomal dominant congenital cataract

Objective Two genes are determined to be relevant to autosomal dominant congenital cataract （ADCC）. Methods Blood samples of a families afflicted with congenital cataracts were collected from the probands and available family members. Selected functional candidate genes were amplified by polymerase chain reaction （PCR） .Two point LOD scores were calculated using the Linkage program. Results Twenty three patients were identified in this family by linkage analysis and clinical examination.All selected micro satellite markers were not co-segregated with the phenotype in this family.LOD scores showed negative values. No linkage relation was found between the pathogenic gene and 23 ADCC candidate genes. Conclusions All known ADCC locus were excluded in this family. Further study should be curried out for the screen of another gene or locus associated to ADCC.