Autosomal dominant retinitis pigmentosa with rhodopsin, valine-345-methionine.

Rhodopsin gene mutations appear to cause some forms of autosomal dominant retinitis pigmentosa. In the family described, the mutation called rhodopsin, Val345Met segregated perfectly with the disease. All affected individuals had abnormal ERGs; the two oldest members of this family had more loss of function than the two youngest members. Some intra-familial variability existed as an older member showed larger visual fields and ERG amplitudes than a younger member. This mutation was not seen in 106 control subjects nor in any other patients yet described with other rhodopsin gene mutations. Patients so far studied with rhodopsin, Val345Met, have smaller 0.5-Hz full-field ERG amplitudes, on average, than those with Pro23His or Thr58Arg and larger ERG amplitudes than those with Pro347Leu or Pro347Ser. These forms of retinitis pigmentosa can now be detected through analysis of leukocyte DNA.