C1QTNF9B

Chr 13

C1q and TNF related 9B

Also known as: CTRP9B

NCBI Gene: 387911 ENSG00000205863 UniProt: B2RNN3

The protein functions as an adipokine that activates AMPK, AKT, and p44/42 MAPK signaling pathways and positively regulates cellular response to insulin stimulus. Mutations cause autosomal recessive intellectual disability with seizures and growth retardation. The gene shows low constraint to loss-of-function variation.

ResearchSummary from RefSeq, UniProt

Predicted to enable hormone activity and identical protein binding activity. Predicted to act upstream of or within several processes, including negative regulation of cell size; positive regulation of cellular response to insulin stimulus; and positive regulation of protein serine/threonine kinase activity. Predicted to be located in obsolete extracellular space. [provided by Alliance of Genome Resources, Jun 2026]

ResearchGenerating clinical summary…

Active trials

Pubs (1 yr)

—

P/LP submissions

—

P/LP missense

1.50

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?

1.50LOEUF

pLI 0.000

Z-score 0.23

OE 0.93 (0.59–1.50)

Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint?

0.18Z-score

OE missense 0.96 (0.85–1.09)

176 obs / 182.9 exp

Tolerant

Mild missense constraint

Observed / Expected Ratios?

LoF OE?0.93 (0.59–1.50)

0≤0.351.4

Missense OE?0.96 (0.85–1.09)

0≤0.61.4

Synonymous OE?1.02

0≤1.21.6

LoF obs/exp: 12 / 12.9Missense obs/exp: 176 / 182.9Syn Z: -0.12

Background carrier burden — how many people carry a rare variant somewhere in C1QTNF9B?

gnomAD v4 · ~731k individuals · PASS only

Rare means allele frequency under

Rare missense

1 in 86

253 rare PASS variants

Rare truncating (LoF)

1 in 860

36 rare PASS variants

Rare synonymous (reference)

1 in 160

99 rare PASS variants

Truncating variants are far rarer here than missense — that gap, in human units, is what constraint means for C1QTNF9B. 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 1,600
South Asian	~43k	1 in 87	1 in 240
Remaining (unassigned)	~30k	1 in 85	1 in 500
European (Finnish)	~27k	1 in 440	1 in 3,300
Admixed American	~22k	1 in 100	1 in 490
African / African American	~21k	1 in 93	1 in 1,400
East Asian	~20k	1 in 160	1 in 1,200
Ashkenazi Jewish	~13k	1 in 400	≈ 1 in 12,000
Middle Eastern	~2,884	1 in 120	≈ 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): 2 of 3 coding exons well covered in gnomAD exomes; exon 4 marginal. Genomes: 2 of 3 (exon 4 below).? see exons ↓