A loxP site flanked neomycin resistance gene cassette was inserted into intron 8 and an exon 9 was modified to change arginine codon 345 (CGA) to tryptophan (TGG) (p.R345W). The neo cassette was removed through subsequent Cre-mediated recombination. The mutation is the equivalent of the same human mutation associated with age-related macular degeneration (AMD). mRNA is expressed at levels equal to wild-type and protein levels in the eyes are similar to wild-type. (J:129901)