NR2E1 and MMEP syndrome: Here, we test the hypothesis that patients with MMEP or a related phenotype may harbor mutations in NR2E1 and/or SNX3. To test this hypothesis, we sequenced the entire NR2E1 coding region, consensus splice-site regions, complete 5' and 3' untranslated regions and evolutionarily conserved elements including core and proximal promoter in one patient with MMEP, three patients with possible MMEP or related phenotypes, and one patient with oligodactyly, ulnar aplasia, and a t(6;7)(q21;q31.2) translocation [11].