NMNAT1 and inherited retinal dystrophy: Infantile cohort. In the 0–6-year-olds, 32.4% of the isolated retinal dystrophies were attributable to disease-causing mutations in “LCA” genes (RPE65 (11%), CEP290 (8.2%), NMNAT1 (4.1%), RDH12 and CRB1 (2.7% each), RPGRIP1, GUCY2D, and LRAT (1.4% each)), and 31.5% were attributed to stationary IRDs.