Abstract
Rearrangements of the X-chromosome cone opsin genes arising from meiotic recombination in females is the cause of common inherited red-green color vision deficiencies. Recent work has revealed that mutation pressure associated with the recombination of the L and M genes has produced deleterious cone opsins responsible for a surprising variety of vision disorders in addition to color vision defects. Some of the mutations affect protein function, while others affect splicing of the pre-messenger RNA. The disorders associated with opsin mutations include high-grade myopia and cone dystrophy. Many of these cone-based vision disorders may be amenable to gene therapy. Some recent efforts aimed at making gene therapy practical and effective for cone-based vision disorders, include, efforts to 1) better understand how gene therapy may effectively take advantage of the inherent learning ability of the cortex to treat vision disorders in adults and 2) develop more effective ways to safely transduce cones by introducing vectors carrying therapeutic genes into the vitreous.