Mutations Analysis Of CRX Gene In Chinese Patients With Retinitis Pigmentosa

Objective To identify the mutations of CRX gene in the patients with rentinitispigmentosa (RP) in Ningxia Hui Autonomous Region and to evaluate their potentialinteraction in the pathogenesis of RP.Methods100individuals with RP were recruited for this study from October2009toNovember2010. Based on family history,18%of the patients classified as ADRP. All patientsreceivied complete ophthalmologic examinations. Polymerase chain reaction (PCR) and directDNA sequencing were used to screen in the entire coding region and splice sites of CRX gene.For rare missense variants detected exclusively in patients, we used four web-based PolyPhenprograms to predict the impact of each amino acid substitution on the structure and functionof the CRX protein. Multiple analysis was used to examine the results.Results In total,5sequence changes in the CRX gene was identified,2synonymouschanges(p.Leu78Leu and p.Ala92Ala),3(p.Ala112Val，p.Gly122Asp and p.Thr187Ile)weremissense changes. p.Ala112Val，p.Gly122Asp were CRX gene polymorphism and showed nopositive correlation with the RP confirmed by the multivariate logistic regression.A missensechange p.Thr187Ile was found in two RP patients.This variation was not deteced in100normal controls. Thr187Ile was predicted to be begin with PSIC and less likely pathogenic.There was no correlation between Thr187Ile variant and RPby Multiple analysis.Conclusions In this study, CRX gene was not associated with RP in Ningxiapopulation.The frequency of CRX mutation in Ningxia RP patients was less than1%. p.Thr187Ile variant was not involved in the pathogenesis with RP,but it may be a modifier forRP.