Exon 14 was replaced with a loxP site and a modified exon 14 in which a C to G transversion results in the amino acid substitution of arginine for serine at position 163 (S163R). An FRT-flanked neo cassette with a 3' loxP site was inserted downstream of the modified exon 14. This mutation is found in Late-Onset Retinal Macular Degeneration (L-ORMD) patients. Flp-mediated recombination removed the neo cassette. (J:180961)