POLYMORPHISM IN THE MURINE TR2-11 GENE ENCODING AN ORPHAN RECEPTOR, AND ITS EXCLUSION AS A CANDIDATE GENE FOR THE CATARACT MUTATION CAT3

Since the dominant cataract mutation Cat3 was mapped very closely to t he murine nuclear receptor Tr2-11 gene locus, the corresponding coding region was amplified by PCR using either genomic DNA or eye-derived c DNA of wild-type (C3Hx102)F-1 and of homozygous Cat3 cataract animals. The analysis of the complete coding sequences showed no differences. Additionally, the expression level was very similar. Therefore, Tr2-11 was excluded as a candidate for the Cat3 mutation. Surprisingly, the obtained sequences exhibited significant alterations to the murine Tr2 -11 sequence reported previously (Lee et al., Genomics 30, 1995, 46-52 ). The differences in the DNA sequence predict remarkable secondary an d tertiary structure alterations of the corresponding protein, The str ucture model of the new Tr2-11 protein is very similar to related rece ptors.