A mouse Rpgr ORF15 variant cDNA was inserted between the cytomegalovirus (CMV) enhancer promoter and the polyadenylation sequence of bovine growth hormone. The cDNA used in this construct is shortened by 654 base pairs in the purine-rich region of the ORF15 exon when compared to the published sequence of the 129/Sv mouse strain. This construct was used to generate transgenic mice by pronuclear injection. Transgene protein accumulates to a much lower level than the endogenous protein and migrated at a size smaller than the native protein.