NR2E1 and Autosomal dominant optic atrophy, classic type: Patients LR00-204 and LR03-277 also represent compound heterozygotes for patient variants of NR2E1. Interestingly, LR00-204, who had microcephaly, was also diagnosed with optic nerve hypoplasia, a phenotype observed in Nr2e1−/− mice (Young et al. 2002; Yu et al. 2000).