Genetic study of retinitis pigmentosa in China.

A total of 190 patients (379 eyes), from 169 families, with retinitis pigmentosa were studied in four genetic aspects in China. A large percentage (58.9%) of affected patients appear to be sporadic cases with no family history of disease. In dermatoglyphic analysis, comparing with the controls, the increment of eight or more whorls, the increase of the number of simian and the value of atd angle in 110 patients with retinitis pigmentosa were statistically significant. In addition, the incidence of G6PD deficiency in retinitis pigmentosa (7.89%) is higher than that (3.5%) of a nonaffected population in the same area. However, there is no significant difference of ABO blood typing between 176 patients with retinitis pigmentosa and the normal population of China.