Kannabiran C, Balasubramanian D
L.V. Prasad Eye Institute, L.V. Prasad Marg, Banjara Hills, Hyderabad-500 034, India.
Indian J Ophthalmol. 2000 Mar;48(1):5-13.
Studies on hereditary congenital cataracts have led to the identification of genes involved in formation of these cataracts. Knowledge of the structure and function of a particular gene and the effect of disease-associated mutations on its function are providing insights into the mechanisms of cataract. Identification of the disease gene requires both the relevant clinical data as well as genetic data on the entire pedigree in which the disease is found to occur. Genes for hereditary cataract have been mapped by genetic linkage analysis, in which one examines the inheritance pattern of DNA markers throughout the genome in all individuals of the pedigree, and compares those with the inheritance of the disease. Cosegregation of a set of markers with disease implies that the disease gene is present at the same chromosomal location as those markers. The genes so far identified for hereditary cataracts in both humans and animal models encode structural lens proteins, gap junction proteins, membrane proteins and regulatory proteins involved in lens development. Understanding of the mechanisms of hereditary cataract may also help us understand the manner in which environmental and nutritional factors act on the lens to promote opacification.
对遗传性先天性白内障的研究已促成了与这些白内障形成相关基因的识别。了解特定基因的结构与功能以及疾病相关突变对其功能的影响，正为白内障的发病机制提供深入见解。疾病基因的识别既需要相关临床数据，也需要在发现该疾病的整个家系中的遗传数据。遗传性白内障的基因已通过遗传连锁分析进行定位，在此分析中，研究人员会检测家系中所有个体整个基因组中DNA标记的遗传模式，并将其与疾病的遗传情况进行比较。一组标记与疾病的共分离意味着疾病基因与那些标记位于相同的染色体位置。目前在人类和动物模型中已识别出的遗传性白内障基因，编码参与晶状体发育的结构晶状体蛋白、间隙连接蛋白、膜蛋白和调节蛋白。对遗传性白内障发病机制的理解，或许还能帮助我们了解环境和营养因素作用于晶状体以促使其混浊的方式。
