NM_000329.3(RPE65):c.331C>T is a missense variant causing substitution of proline with serine at position 111. This variant is present in gnomAD v.2.1.1 at a GrpMax allele frequency of 0.00003249, with 4 alleles / 41440 total alleles in the African/African American population, which is lower than the ClinGen LCA / eoRD VCEP PM2_Supporting threshold of <0.0002 (PM2_Supporting). The computational predictor REVEL gives a score of 0.911, which is above the ClinGen LCA / eoRD VCEP threshold of ≥ 0.773 and predicts a damaging effect on RPE65 function (PP3_Moderate). This variant is located within a well-established functional domain (residues 107-125, PMID: 36265895) required for proper localization of the RPE65 protein to the ER membrane (PM1). This variant has been reported in at least 1 proband with early-onset severe retinal dystrophy who was homozygous for the variant (0.5, PMID: 34492281). This variant has also been reported in at least 2 probands with early-onset severe retinal dystrophy who were compound heterozygous with either the NM_000329.2:c.11+5G>A or NM_000329.2:c.1451G>A (p.Gly484Asp) variants confirmed in trans (2 pts, PMIDs: 34492281), which were previously classified as pathogenic or likely pathogenic by the ClinGen LCA / eoRD VCEP (2.5 total points, PM3_Strong). At least one proband harboring this variant exhibits a phenotype including diagnosis with Leber congenital amaurosis (0.5 pts) with onset before age 1 year (1 pt), reduced ERG responses from rods (0.5 pts) and cones (1 pt), salt and pepper pigmentation of the fundus (0.5 pts), visual fields decreased (1 pt), visual acuity reduced (1 pt), and night blindness (0.5 pts), which together are specific for RPE65-related recessive retinopathy (6 points, PMID: 34492281, PP4). The variant has been reported to segregate with childhood-onset severe retinal dystrophy through the proband plus 1 similarly affected relative, with the variant present in the homozygous state (PP1; PMID: 34492281). In summary, this variant meets the criteria to be classified as pathogenic for RPE65-related recessive retinopathy based on the ACMG/AMP criteria applied, as specified by the ClinGen LCA / eoRD VCEP: PM1, PM2_Supporting, PM3_Strong, PP1, PP3_Moderate, and PP4. (VCEP specifications version 1.0.0; date of approval 09/21/2023).