TACO1

Chr 17AR

translational activator of cytochrome c oxidase I

Also known as: CCDC44, MC4DN8

NCBI Gene: 51204 ENSG00000136463 UniProt: Q9BSH4 OMIM: 612958

The protein functions as a translational activator of mitochondrially-encoded cytochrome c oxidase 1. Mutations cause mitochondrial complex IV deficiency (nuclear type 8) and Leigh syndrome through autosomal recessive inheritance.

GeneReviews OMIM ResearchSummary from RefSeq, OMIM, UniProt

This gene encodes a mitochondrial protein that function as a translational activator of mitochondrially-encoded cytochrome c oxidase 1. Mutations in this gene are associated with Leigh syndrome.[provided by RefSeq, Mar 2010]

GeneReviews OMIM ResearchGenerating clinical summary…

LOFmechanismARLOEUF 1.091 OMIM phenotype

Clinical Summary— TACO1

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Gene-Disease Validity (ClinGen)

Leigh syndrome · ARModerate

Moderate evidence — consider for supplementary testing

2 total gene-disease associations curated

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Population Constraint (gnomAD)

Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.

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ClinVar Variants

16 unique Pathogenic / Likely Pathogenic· 98 VUS of 184 total submissions

Explore recent and relevant literature in Research Assistant →

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GeneReview available — TACO1

Authoritative clinical overview · Recommended first read

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Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

gnomAD

Tolerant — LoF & missense variants common in population

LoF Constraint?

1.09LOEUF

pLI 0.001

Z-score 1.37

OE 0.55 (0.30–1.09)

Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint?

0.94Z-score

OE missense 0.80 (0.69–0.92)

133 obs / 167.1 exp

Tolerant

Mild missense constraint

Observed / Expected Ratios?

LoF OE?0.55 (0.30–1.09)

0≤0.351.4

Missense OE?0.80 (0.69–0.92)

0≤0.61.4

Synonymous OE?1.09

0≤1.21.6

LoF obs/exp: 6 / 10.9Missense obs/exp: 133 / 167.1Syn Z: -0.57

ClinVar Variant Classifications

184 submitted variants in ClinVar

ClinVar

Classification Summary

Pathogenic2

Likely Pathogenic14

VUS98

Likely Benign50

Benign9

Conflicting7

Pathogenic

Likely Pathogenic

VUS

Likely Benign

Benign

Conflicting

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

Classification	LoF	Missense + Inframe	Non-coding	Synonymous	Total
Pathogenic	2	0	0	0	2
Likely Pathogenic	13	1	0	0	14
VUS	1	82	12	3	98
Likely Benign	0	4	15	31	50
Benign	0	1	8	0	9
Conflicting	—				7
Total	16	88	35	34	180

LoF = frameshift, stop gained/lost, canonical splice · Counts from ClinVar esearch · Updated hourly

View in ClinVar →

10 pathogenic / likely-pathogenic (of 11) ClinVar copy-number / structural variants overlap TACO1 — these span large chromosomal regions, not the gene specifically, and are excluded from the counts above. Explore in CNV tools →