[A study on the rhodopsin gene in Japanese retinitis pigmentosa--screening of mutation by restriction endonucreases and frequencies of DNA polymorphisms].

We analyzed 11 sites of the rhodopsin gene using polymerase chain reaction (PCR) amplification and restriction endonucleases in 30 unrelated Japanese patients with autosomal dominant retinitis pigmentosa (ADRP). No point mutation was found in any patient. The frequencies of the single nucleotide (nt) substitution at nt 269, nt 5145 and nt 5321 were examined in three groups, 38 unrelated patients with ADRP, 23 patients with autosomal recessive retinitis pigmentosa (ARRP), and 67 normal controls. There was no significant difference in the frequencies of substitution among these three groups. The frequencies of A269G, G5145A, and C5321A were 52%, 36%, and 5%, respectively. These values were different from those of the American population. The polymorphisms, A269G and G5145A, are useful as DNA makers for linkage analysis.