Lens biology: development and human cataractogenesis.

Cataract, or opacification of the lens of the eye, is the commonest cause of visual impairment world-wide. It is only treatable at present by surgical removal. Recent advances in our understanding of the genetics of human cataract, in particular the inherited congenital form, together with the development of an array of animal models have provided valuable new insights into normal vertebrate lens biology and the mechanisms that underlie cataract formation. In this article, we review the current state of research in these areas and discuss thinking regarding the relationship between the phenotypes observed and the underlying genotype in inherited cataract.