Rpgr KO Mouse

The Retinitis Pigmentosa GTPase Regulator (RPGR) gene, located on the X chromosome (Xp11.4), is crucial for normal vision and is ubiquitously expressed across various tissues, including the retina, brain, lung, kidney, and testis. It undergoes complex alternative splicing, producing numerous isoforms, with RPGRORF15 being the major isoform predominantly expressed in photoreceptor cells of the retina ^[1]. The RPGR protein, which localizes to cellular structures called cilia (specifically the connecting cilium of photoreceptors, and the transition zone of other ciliated tissues), is thought to regulate protein trafficking and maintain the function of these cilia ^[2]. Mutations in RPGR are the most common cause of X-linked retinitis pigmentosa (XLRP), a severe inherited retinal dystrophy characterized by progressive degeneration of rod and cone photoreceptors, leading to night blindness in childhood followed by progressive vision loss and eventual blindness ^[3]. RPGR mutations can also lead to other retinal disorders such as X-linked cone-rod dystrophy (CORDX1) and, in some cases, syndromic presentations involving chronic respiratory and sinus infections, recurrent ear infections, and hearing loss, collectively known as primary ciliary dyskinesia (PCD) with RP, due to the widespread role of RPGR in ciliary function ^[1-3].

The Rpgr KO mouse is a gene knockout model created using gene-editing techniques to knock out the coding sequence of the Rpgr gene (the homolog of the human RPGR gene) in mice. This model can be used to study the pathogenic mechanisms of retinal diseases like X-linked retinitis pigmentosa (XLRP) and X-linked cone-rod dystrophy (CORDX1), providing a research basis for developing related therapeutic interventions.