Objective: To detect the disease-causing mutation in a pedigree affected with autosomal dominant congenital cataract.
Methods: Genomic DNA was extracted and purified from peripheral blood samples from members of the pedigree and 100 healthy controls. Coding regions of 18 candidate genes were screened with PCR and Sanger sequencing. Identified mutations were verified among 100 healthy individuals to exclude single nucleotide polymorphisms.
Results: A heterozygous nonsense mutation c.471G>A of the CRYGD gene, which resulted in p.Trp157Term, was identified in all three patients. The same mutation was not found in the two normal individuals from the family and 100 healthy controls. The nonsense mutation was predicted to be "disease causing" by Mutation t@sting program.
Conclusion: The nonsense mutation c.471G>A of the CRYGD gene probably underlies the congenital cataract in the pedigree.