Complex IV assembly gene disorders include SURF1 (Surfeit locus protein 1), associated with Leigh Syndrome;128,129C12ORF62 (chromosome 12 open reading frame 62), associated with fatal, neonatal, mitochondrial IV deficiency;130COA5 (cytochrome c oxidase assembly factor 5), associated with neonatal hypertrophic cardiomyopathy131 and FASTKD2, associated with cytochrome c oxidase-defective encephalomyopathy.132. This evidence concerns the gene SURF1 and Leigh syndrome.