C19orf12 and neurodegeneration with brain iron accumulation 4: While the number of causative genes is increasing, major NBIA disorders comprise pantothenate kinase-associated neurodegeneration (PKAN) caused by mutation in the PANK2 gene, mitochondrial membrane protein-associated neurodegeneration (MPAN) caused by mutation in the C19orf12 gene, beta-propeller protein-associated neurodegeneration (BPAN) due to WDR45 mutation, and phospholipase A2 type G6 (PLA2G6)-associated neurodegeneration (PLAN) due to PLA2G6 mutations (reviewed in [2,167,168,169,170,171,172]).