Retinitis pigmentosa (RP) is the most common hereditary retinal degeneration and an important cause of visual disability worldwide. It has complex genetic basis and multiple genes are involved in the pathogenesis of RP. Rhodopsin gene is one the most important genes implicated in RP, especially in patients with autosomal dominant inheritance (ADRP). In this study, we investigated rhodopsin gene mutations in Iranian patients with ADRP

21 patients from 21 unrelated families were enrolled in the study. After complete history taking and ophthalmic examination and genetic counseling, peripheral blood samples were obtained for genetic testing. Direct sequencing was performed on cloned exons of rhodopsin gene. Polyphen software was used to analyze the functional effect of novel mutations to predict their pathogenicity.

results of direct sequencing revealed that 5 of 21 patients (23.8%) had mutation in the rhodopsin gene. 2 of them had previously identified p.P347L mutation and 3 had novel mutations including p.P95L, p.R177K and p.N310K. analysis by Polyphen software showed that all of three novel mutations were pathogenic with more than 99% confidence. The L95P mutation was associated with predominantly inferior retinal involvement

our study showed that mutations of rhodopsin gene are relatively frequent in Iranian patients with ADRP and could be considered in researches in the future. The novel L95P mutation may be associated with specific pattern of retinal degeneration in this population