INAD is caused by homozygous or compound heterozygous mutations in the PLA2G6 gene that encodes phospholipase A2, group VI (Khateeb et al., 2006; Morgan et al., 2006): the mitochondrial pathology and degeneration of presynaptic membranes underlie INAD pathology (Beck et al., 2011; Sumi-Akamaru et al., 2015). Here, PLA2G6 is linked to neurodegeneration with brain iron accumulation 2A.