CCDC83

Chr 11

coiled-coil domain containing 83

Also known as: CT148, HSD9, KP-CoT-23

NCBI Gene: 220047 ENSG00000150676 UniProt: Q8IWF9

This gene encodes a coiled-coil domain containing protein of unknown function. Mutations cause autosomal recessive intellectual disability with seizures and dysmorphic features. The gene shows minimal constraint against loss-of-function variants, which is consistent with the recessive inheritance pattern observed in affected individuals.

Research

ResearchGenerating clinical summary…

Active trials

Pubs (1 yr)

—

P/LP submissions

—

P/LP missense

1.10

LOEUF

Multiple*

Mechanism· predicted

Some data sources returned errors (1)

omim: Error: OMIM fetch failed: 429

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

gnomAD

Tolerant — LoF & missense variants common in population

LoF Constraint?

1.10LOEUF

pLI 0.000

Z-score 1.18

OE 0.73 (0.50–1.10)

Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint?

-0.45Z-score

OE missense 1.09 (0.98–1.21)

239 obs / 220.1 exp

Tolerant

Tolerant to missense variation

Observed / Expected Ratios?

LoF OE?0.73 (0.50–1.10)

0≤0.351.4

Missense OE?1.09 (0.98–1.21)

0≤0.61.4

Synonymous OE?0.98

0≤1.21.6

LoF obs/exp: 17 / 23.1Missense obs/exp: 239 / 220.1Syn Z: 0.13

Background carrier burden — how many people carry a rare variant somewhere in CCDC83?

gnomAD v4 · ~731k individuals · PASS only

Rare means allele frequency under

Rare missense

1 in 82

598 rare PASS variants

Rare truncating (LoF)

1 in 1,100

123 rare PASS variants

Rare synonymous (reference)

1 in 400

191 rare PASS variants

Truncating variants are far rarer here than missense — that gap, in human units, is what constraint means for CCDC83. 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)	~556k	1 in 130	1 in 1,300
South Asian	~43k	1 in 110	1 in 970
Remaining (unassigned)	~30k	1 in 85	1 in 780
European (Finnish)	~27k	1 in 570	1 in 3,800
Admixed American	~22k	1 in 78	1 in 1,100
African / African American	~21k	1 in 67	1 in 1,400
East Asian	~20k	1 in 110	1 in 1,800
Ashkenazi Jewish	~13k	1 in 1,000	≈ 1 in 12,000
Middle Eastern	~2,884	1 in 87	1 in 410

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): 7 of 10 coding exons well covered in gnomAD exomes; exons 2, 3, 6 marginal. Genomes: 9 of 10 (exon 6 below).? see exons ↓