TTC19

Chr 17AR

tetratricopeptide repeat domain 19

Also known as: 2010204O13Rik, MC3DN2

The protein is embedded in the inner mitochondrial membrane and is involved in the formation of mitochondrial respiratory chain complex III. Mutations cause mitochondrial complex III deficiency, nuclear type 2, inherited in an autosomal recessive pattern. The pathogenic mechanism is predicted to be gain of function.

GeneReviewsOMIMResearchSummary from RefSeq, OMIM, UniProt, Mechanism
LOFmechanismARLOEUF 1.121 OMIM phenotype
Clinical SummaryTTC19
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Gene-Disease Validity (ClinGen)
Leigh syndrome · ARDefinitive

Definitive — sufficient evidence for diagnostic panels

2 total gene-disease associations curated

Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.
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ClinVar Variants
54 unique Pathogenic / Likely Pathogenic· 208 VUS of 456 total submissions
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GeneReview available — TTC19
Authoritative clinical overview · Recommended first read
Open GeneReview ↗

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint
1.12LOEUF
pLI 0.000
Z-score 1.16
OE 0.73 (0.481.12)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint
0.08Z-score
OE missense 0.98 (0.871.11)
176 obs / 179.1 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios
LoF OE0.73 (0.481.12)
00.351.4
Missense OE0.98 (0.871.11)
00.61.4
Synonymous OE1.19
01.21.6
LoF obs/exp: 15 / 20.7Missense obs/exp: 176 / 179.1Syn Z: -1.21
Curated Mechanism (G2P)Gene2Phenotype (DDG2P) ↗
definitiveTTC19-related mitochondrial complex III deficiencyLOFAR

Predictions shown for reference only — model trained on dominant genes, not applicable to AR conditions.

DN
0.6552th %ile
GOF
0.6443th %ile
LOF
0.2871th %ile

The Badonyi & Marsh prediction model was trained exclusively on dominant disease genes. Predictions are not reliable for genes with autosomal recessive inheritance and are shown at reduced opacity for reference only.

Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.

ClinVar Variant Classifications

456 submitted variants in ClinVar

Classification Summary

Pathogenic42
Likely Pathogenic12
VUS208
Likely Benign116
Benign38
Conflicting24
42
Pathogenic
12
Likely Pathogenic
208
VUS
116
Likely Benign
38
Benign
24
Conflicting

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
14
0
28
0
42
Likely Pathogenic
11
1
0
0
12
VUS
6
115
83
4
208
Likely Benign
0
8
64
44
116
Benign
1
0
35
2
38
Conflicting
24
Total3212421050440

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

View in ClinVar →

Protein Context — Lollipop Plot

TTC19 · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

3D Protein StructureAlphaFold

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

No active trials found for this gene.

Search ClinicalTrials.gov →
Clinical Literature
Open Research Assistant →