A Homozygous 1-Base Pair Deletion (1147dela) in the Arrestin Gene in Autosomal Recessive Retinitis Pigmentosa

Abstract

Retinitis pigmentosa (RP) is a genetically heterogeneous group of diseases that show progressive degeneration of photoreceptors. Its incidence is about one in 3000 to 10,000 people in many countries, and it is a leading cause of blindness in the adult population. Several kinds of mutations have been reported in patients with autosomal recessive RP (arRP) in genes that are normally expressed in rod photoreceptors and that function in the process of phototransduction. Arrestin, one of the photoreceptorspecific proteins, plays a role in the cycle of rhodopsin regeneration. 1 A homozygous 1-base pair deletion mutation in the arrestin gene, designated the arrestin 1147delA, has been known as a frequent cause of Oguchi disease, a form of congenital stationary night blindness, in Japanese patients. 2 Interestingly, molecular genetic screening in patients with arRP, including a sibling of a patient with Oguchi disease, to search for mutations in the arrestin gene revealed that the same 1147delA mutation is also associated with arRP and is cosegregated with the disease. We report on 3 patients with arRP associated with the homozygous 1147delA mutation in the arrestin gene as evidence of variable expressivity of the mutation in the arrestin gene.