A Study on X-Linked Retinitis Pigmentosa and Its Molecular Diagnosis

Purpose: Retinitis pigmentosa (RP) is a hereditary eye disease in human beings. It commences at childhood and continues by Nyctalopia and gradual reduction of visual field and ends up by blindness. It may be inherited in three forms of autosomal dominant, autosomal recessive and sex-linked. In this investigation we intend to study RP type as a sex-linked disease and its location on X chromosome. Case report: Upon blood taking and extraction of DNA by the use of PCR method, it was possible to reproduce RPGR gene. Then the PCR product was subject to electrophoresis on Agarose Gel. Results: The patient is a 12-year-old and blind boy with Ataxia. The diagnosis was RP3. We found a mutation in Exon No. 5 of RPGR gene related to regulating GTPase enzyme through which TCA code of Serine Amino Acid is replaced with TTA code of Aminoacid Lysine. As a result there will be a change in protein chain with further disorders in GTPase function. Conclusion: The mutation in Exon No. 5 of RPGR gene causing a change in protein chain and disorders in GTPase function.