TAS1R3

Chr 1

taste 1 receptor member 3

Also known as: T1R3

NCBI Gene: 83756 ENSG00000169962 UniProt: Q7RTX0

The protein is a G-protein coupled receptor that forms heterodimeric taste receptors, combining with TAS1R1 to detect umami taste stimuli or with TAS1R2 to recognize sweet compounds including natural and synthetic sweeteners. The gene shows very low constraint against loss-of-function variants, and no clear Mendelian diseases have been established from TAS1R3 mutations based on the available data.

ResearchSummary from RefSeq, UniProt

The protein encoded by this gene is a G-protein coupled receptor involved in taste responses. The encoded protein can form a heterodimeric receptor with TAS1R1 to elicit the umami taste response, or it can bind with TAS1R2 to form a receptor for the sweet taste response. [provided by RefSeq, Nov 2015]

ResearchGenerating clinical summary…

Active trials

Pubs (1 yr)

—

P/LP submissions

—

P/LP missense

1.56

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?

1.56LOEUF

pLI 0.000

Z-score -0.87

OE 1.18 (0.89–1.56)

Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint?

-2.38Z-score

OE missense 1.28 (1.20–1.36)

732 obs / 571.7 exp

Tolerant

Tolerant to missense variation

Observed / Expected Ratios?

LoF OE?1.18 (0.89–1.56)

0≤0.351.4

Missense OE?1.28 (1.20–1.36)

0≤0.61.4

Synonymous OE?1.40

0≤1.21.6

LoF obs/exp: 34 / 28.9Missense obs/exp: 732 / 571.7Syn Z: -5.24

Background carrier burden — how many people carry a rare variant somewhere in TAS1R3?

gnomAD v4 · ~730k individuals · PASS only

Rare means allele frequency under

Rare missense

1 in 23

1,509 rare PASS variants

Rare truncating (LoF)

1 in 280

207 rare PASS variants

Rare synonymous (reference)

1 in 43

756 rare PASS variants

Truncating variants are far rarer here than missense — that gap, in human units, is what constraint means for TAS1R3. 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 28	1 in 690
South Asian	~43k	1 in 23	1 in 390
Remaining (unassigned)	~30k	1 in 20	1 in 310
European (Finnish)	~26k	1 in 60	1 in 560
Admixed American	~22k	1 in 24	1 in 440
African / African American	~21k	1 in 20	1 in 230
East Asian	~20k	1 in 27	1 in 420
Ashkenazi Jewish	~13k	1 in 89	≈ 1 in 4,300
Middle Eastern	~2,884	1 in 25	1 in 320

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 6 coding exons well covered in gnomAD exomes and genomes.? see exons ↓