PET117

Chr 20AR

PET117 cytochrome c oxidase chaperone

Also known as: CSRP2BP, MC4DN19

NCBI Gene: 100303755 ENSG00000232838 UniProt: Q6UWS5 OMIM: 614771

PET117 encodes a protein involved in mitochondrial cytochrome c oxidase assembly within the mitochondrion. Mutations cause mitochondrial complex IV deficiency, nuclear type 19, which follows autosomal recessive inheritance. The gene shows low constraint to loss-of-function variants, consistent with its recessive disease pattern.

OMIM ResearchSummary from RefSeq, OMIM

Predicted to be involved in mitochondrial respiratory chain complex IV assembly. Located in mitochondrion. Implicated in mitochondrial complex IV deficiency nuclear type 19. [provided by Alliance of Genome Resources, Jun 2026]

OMIM ResearchGenerating clinical summary…

Primary Disease Associations & Inheritance

?Mitochondrial complex IV deficiency, nuclear type 19MIM #619063

Clinical highlights

Gene–disease validity (ClinGen)

not for standalone diagnostic reporting

Active trials

Pubs (1 yr)

—

P/LP submissions

—

P/LP missense

1.83

LOEUF

Multiple*

Mechanism· predicted

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

gnomAD

Tolerant — LoF & missense variants common in population

LoF Constraint?

1.83LOEUF

pLI 0.032

Z-score 0.26

OE 0.82 (0.32–1.83)

Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint?

0.47Z-score

OE missense 0.78 (0.58–1.07)

28 obs / 35.9 exp

Tolerant

Mild missense constraint

Observed / Expected Ratios?

LoF OE?0.82 (0.32–1.83)

0≤0.351.4

Missense OE?0.78 (0.58–1.07)

0≤0.61.4

Synonymous OE?1.29

0≤1.21.6

LoF obs/exp: 2 / 2.4Missense obs/exp: 28 / 35.9Syn Z: -0.81

Background carrier burden — how many people carry a rare variant somewhere in PET117?

gnomAD v4 · ~692k individuals · PASS only

Rare means allele frequency under

Rare missense

1 in 360

104 rare PASS variants

Rare truncating (LoF)

1 in 5,200

23 rare PASS variants

Rare synonymous (reference)

1 in 1,800

46 rare PASS variants

Truncating variants are far rarer here than missense — that gap, in human units, is what constraint means for PET117. A background rate for each class, not the frequency of any particular variant; thin-coverage exons undercount.

By genetic ancestry · 9 gnomAD groups · rare = under 0.1% in that group

Group	People	Missense	Truncating
European (non-Finnish)	~539k	1 in 840	1 in 4,500
South Asian	~40k	1 in 690	≈ 1 in 40,000
Remaining (unassigned)	~29k	1 in 370	≈ 1 in 9,500
African / African American	~21k	1 in 880	1 in 1,700
East Asian	~18k	1 in 490	none seen
Admixed American	~18k	1 in 580	≈ 1 in 5,100
European (Finnish)	~18k	1 in 2,400	≈ 1 in 17,000
Ashkenazi Jewish	~13k	≈ 1 in 5,900	none seen
Middle Eastern	~2,848	1 in 470	≈ 1 in 1,400

Each group is summed over the variants that are rare in that group. Grey ≈ figures rest on fewer than five expected carriers — too few to distinguish groups. Differences mostly reflect how many people were sampled and how much variation each ancestry carries, not disease risk.

Exome coverage (gnomAD): 1 of 2 coding exons well covered in gnomAD exomes; exon 1 marginal. Genomes: all 2.? see exons ↓