CLONING OF THE CDNA-ENCODING ROD PHOTORECEPTOR CGMP-PHOSPHODIESTERASEALPHA-SUBUNIT AND GAMMA-SUBUNIT FROM THE RETINAL DEGENERATE LABRADOR-RETRIEVER DOG

The nucleotide (nt) sequence of the cDNA encoding the retinal rod cycl ic 3'5'-GMP phosphodiesterase (PDE) alpha and gamma subunits from two strains of dogs - (i) Labrador Retrievers homozygous for autosomally r ecessively inherited rod-cone degeneration and (ii) the wild-type Beag le - are reported. Cloning of these subunits was accomplished by polym erase chain reaction using retinal cDNA libraries as templates. The nt sequence of alpha PDE predicts a 861 amino-acid polypeptide which is 97.7 per cent and 96.9 per cent identical to the bovine and human coun terparts, respectively. PDE gamma encodes an 87-amino-acid polypeptide differing from bovine and murine gamma subunits by only one amino aci d. Since no differences were found between these two strains of dogs, the cause of the Labrador Retriever's degeneration remains to be deter mined.