RHO

About RHO

RHO on chromosome 3q22.1 encodes rhodopsin, the light sensitive pigment of the rod photoreceptors, made up of the protein opsin bound to 11 cis retinal, a derivative of vitamin A. When a photon is absorbed, retinal changes shape and activates a signaling cascade that underlies vision in dim light. Rhodopsin is a G protein coupled receptor and was the first member of this large receptor family to have its crystal structure determined, in 2000. Variants in RHO are the most common cause of autosomal dominant retinitis pigmentosa, a progressive degeneration that begins with night blindness and loss of side vision. The P23H variant, frequent in the United States, causes the protein to misfold. Some RHO variants instead cause congenital stationary night blindness, a non progressive condition. Gene editing and RNA based approaches for RHO disease are being studied.