OR5B21

Chr 11

olfactory receptor family 5 subfamily B member 21

NCBI Gene: 219968 ENSG00000198283 UniProt: A6NL26

Olfactory receptors interact with odorant molecules in the nose, to initiate a neuronal response that triggers the perception of a smell. The olfactory receptor proteins are members of a large family of G-protein-coupled receptors (GPCR) arising from single coding-exon genes. Olfactory receptors share a 7-transmembrane domain structure with many neurotransmitter and hormone receptors and are responsible for the recognition and G protein-mediated transduction of odorant signals. The olfactory receptor gene family is the largest in the genome. [provided by RefSeq, Jul 2008]

Research

ResearchGenerating clinical summary…

Active trials

Pubs (1 yr)

—

P/LP submissions

—

P/LP missense

1.94

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?

1.94LOEUF

pLI 0.000

Z-score -1.05

OE 1.53 (0.80–1.94)

Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint?

-0.05Z-score

OE missense 1.01 (0.89–1.15)

170 obs / 168.3 exp

Tolerant

Tolerant to missense variation

Observed / Expected Ratios?

LoF OE?1.53 (0.80–1.94)

0≤0.351.4

Missense OE?1.01 (0.89–1.15)

0≤0.61.4

Synonymous OE?1.22

0≤1.21.6

LoF obs/exp: 7 / 4.6Missense obs/exp: 170 / 168.3Syn Z: -1.43

Background carrier burden — how many people carry a rare variant somewhere in OR5B21?

gnomAD v4 · ~731k individuals · PASS only

Rare means allele frequency under

Rare missense

1 in 98

419 rare PASS variants

Rare truncating (LoF)

1 in 3,600

52 rare PASS variants

Rare synonymous (reference)

1 in 290

162 rare PASS variants

Truncating variants are far rarer here than missense — that gap, in human units, is what constraint means for OR5B21. 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 140	1 in 5,600
South Asian	~43k	1 in 160	1 in 1,200
Remaining (unassigned)	~30k	1 in 89	1 in 3,800
European (Finnish)	~27k	1 in 330	none seen
Admixed American	~22k	1 in 160	1 in 3,700
African / African American	~21k	1 in 150	1 in 1,500
East Asian	~20k	1 in 120	1 in 1,600
Ashkenazi Jewish	~13k	1 in 1,000	none seen
Middle Eastern	~2,884	1 in 110	none seen

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): All 1 coding exons well covered in gnomAD exomes and genomes.? see exons ↓