NMNAT1 and Leber congenital amaurosis: Among the three known NMNAT enzymes, mutations in the nuclear NMNAT isoform 1 have been identified in several studies as one of the many causes of an early‐onset and progressive form of Leber congenital amaurosis (LCA), a severe blinding retinal disease (Falk et al,2012; Koenekoop et al,2012; Perrault et al,2012; Siemiatkowska et al,2014; Nash et al,2018).