Retinitis pigmentosa genetics: a study in Indian population.

A total of 151 retinitis pigmentosa (RP) patients from 83 families were screened and the frequencies of different genetic categories studied. One hundred and ten patients out of 151 had a positive inheritance pattern, and autosomal recessive (AR) emerged as the predominant (53 out of 151), genetic pattern followed by isolated or sporadic (41 out of 151) cases. Further study of autosomal recessive cases revealed consanguinity as the main characteristic (49 out of 53) in the Indian population studied. Early onset and severe progression of disease was seen in the consanguineous group.