Features include always present findings: Increased circulating pyruvate concentration, Increased circulating lactate concentration, Generalized hypotonia, and Weakness of facial musculature and others; and common findings: Neonatal respiratory distress.

COX6A2 encodes cytochrome c oxidase subunit 6A2 (97 aa). Component of the cytochrome c oxidase, the last enzyme in the mitochondrial electron transport chain which drives oxidative phosphorylation. Highest expression in Muscle Skeletal (2,284 TPM) and Heart Left Ventricle (1,594 TPM).

Mitochondrial complex IV deficiency, nuclear type 18 is associated with mutations in the COX6A2 gene on chromosome 16.

COX6A2 is classified as a druggable target (Enzyme category) with score 0.0.

Genetic testing for COX6A2 is available. Testing is considered confirmatory for diagnosis.

Phenotype severity distribution: 9 always present features, 1 common feature.

No clinical trials have been registered for mitochondrial complex IV deficiency, nuclear type 18.

2 publications have been identified in PubMed for mitochondrial complex IV deficiency, nuclear type 18. Research spans Other (50%) and Basic Science / Preclinical (50%).

Recent Publications

• Zhang L (2025). [PMID: 39716856](https://pubmed.ncbi.nlm.nih.gov/39716856/). *Adv Sci (Weinh)*. [Basic Science / Preclinical]

• Kaiyrzhanov R (2025). [PMID: 39963288](https://pubmed.ncbi.nlm.nih.gov/39963288/). *Brain Commun*. [Other]