Underlined values are claims re-computed from the knowledge base each time this page is built. The tables below are the source of truth.

COQ5 is the mitochondrial 2-methoxy-6-polyprenyl-1,4-benzoquinol methylase (EC 2.1.1.201), a Class I S-adenosyl-L-methionine (SAM)-dependent methyltransferase of the MenG/UbiE family. It catalyzes the sole C-methylation step in the biosynthesis of coenzyme Q (ubiquinone; CoQ10 in humans): using SAM as the methyl donor, it transfers a methyl group onto the C2 position of the polyprenylated benzoquinol ring, producing S-adenosyl-L-homocysteine. In humans this converts 2-methoxy-6-(all-trans-decaprenyl)benzene-1,4-diol to the corresponding methylated product en route to CoQ10. The protein is synthesized with an N-terminal mitochondrial transit peptide and localizes as a peripheral membrane protein on the matrix side of the mitochondrial inner membrane, where it is a component of the multi-subunit COQ enzyme complex (the CoQ synthome / COQ metabolon) together with COQ3, COQ4, COQ6, COQ7 and COQ9. Loss-of-function variants cause autosomal recessive primary coenzyme Q10 deficiency (COQ10D9), presenting with cerebellar ataxia and static encephalomyopathy.

Disorders

Relationship is the entry's genetic[].relationship_type. untyped means the entry has a genetic record for the gene but does not type it; its free-text association is shown instead.

An entry matches when ClinGen's MONDO disease is the entry's own disease term, a subtype term, or an exact-match mapping. An amber status marks an entry ClinGen supports the gene for (Definitive, Strong or Moderate) whose own record does not type it. A Limited, Disputed or Refuted tier on such an entry is not a gap.