Mitochondrial Complex I Deficiency, Nuclear Type 12, also known as mc1dn12, is related to mitochondrial encephalomyopathy. An important gene associated with Mitochondrial Complex I Deficiency, Nuclear Type 12 is NDUFA1 (NADH:Ubiquinone Oxidoreductase Subunit A1). Affiliated tissues include liver and brain, and related phenotypes are ataxia and global developmental delay