Novel Mutations of PAX6 and WFS1 Associated With Congenital Cataract in a Chinese Family

Background: Congenital cataract is a common cause of blindness in childhood. About half of the cases have a genetic etiology, and more than 100 genes have been associated with congenital cataracts. This study reports the clinical and genetic findings of a two-generation Chinese family affected by congenital cataract. Methods: Ophthalmologic examinations were performed for clinical evaluation of the cataract patients. Whole exome sequencing (WES) and Sanger sequencing were used to identify potentially relevant mutations. The online programs Protein Variation Effect Analyzer (PROVEAN) and Sorting Intolerant from Tolerant (SIFT) were employed to predict the impact of variation on protein function. Results: Both the proband and her mother were blind because of bilateral nuclear cataracts, and the elder brother of the proband also manifested obvious bilateral cataracts. Sanger sequencing confirmed the mutations in the proband as well as in her mother. The elder brother simply carried the PAX6 c.221G>A variation. The WFS1 c.2070_2079del variation potentially generates a loss-of-function mutant. Conclusion: The novel PAX6 mutation (c.221G>A) is associated with congenital cataract, and the WFS1 mutation (c.2070_2079del) may interactively aggravates this process. These findings may increase our understanding of the genetic etiology of congenital cataract.