ATXN2 and amyotrophic lateral sclerosis: Included in the 126 ALS genes in the Amyotrophic Lateral Sclerosis Online genetics Database (v6) are one mitochondrial gene (MT-ND2) and 10 nuclear genome-coded mitochondrial genes (ATXN2, CHCHD10, GARS, MAOB, OGG1, OMA1, PARK7, SOD1 SOD2 and SPG7), found when ALS genes are cross-over with MitoCarta [5, 15].