This spontaneous mutation was discovered during a routine strain screen at The Jackson Laboratory. Its mapping location suggested it might be an allele of Rpe65, and a point mutation was identified in the Rpe65 gene. The mutation is a base substitution C-to-T at coding nucleotide 130 resulting in a stop codon in stead of arginine at position 44 (p.R44*). Immunostaining revealed that mutant eyes do not express RPE65 protein, and subretinal injection of the AAV5-CBA viral vector expressing human RPE65 significantly rescued the visual phenotype for at least 7 months following treatment. (J:94549)