SLC22A9

Chr 11

solute carrier family 22 member 9

Also known as: HOAT4, OAT4, OAT7, UST3H, ust3

NCBI Gene: 114571 ENSG00000149742 UniProt: Q8IVM8 OMIM: 607579

The protein functions as a sodium-independent organic anion transporter that specifically transports sulfated conjugates of steroid hormones and xenobiotics, and can exchange these substrates for short-chain fatty acids at hepatocyte membranes. Mutations in this gene are associated with Lynch syndrome and mismatch repair cancer syndrome. The gene shows very low constraint against loss-of-function variants (high LOEUF score), suggesting tolerance to genetic variation.

OMIM ResearchSummary from RefSeq, UniProt

Enables secondary active transmembrane transporter activity and short-chain fatty acid transmembrane transporter activity. Involved in hormone transport; short-chain fatty acid transmembrane transport; and sodium-independent organic anion transport. Located in basolateral plasma membrane. Implicated in Lynch syndrome and mismatch repair cancer syndrome. [provided by Alliance of Genome Resources, Jun 2026]

OMIM ResearchGenerating clinical summary…

Active trials

Pubs (1 yr)

—

P/LP submissions

—

P/LP missense

1.61

LOEUF

Multiple*

Mechanism· predicted

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

gnomAD

Tolerant — LoF & missense variants common in population

LoF Constraint?

1.61LOEUF

pLI 0.000

Z-score -0.72

OE 1.16 (0.85–1.61)

Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint?

-1.24Z-score

OE missense 1.20 (1.10–1.31)

364 obs / 303.2 exp

Tolerant

Tolerant to missense variation

Observed / Expected Ratios?

LoF OE?1.16 (0.85–1.61)

0≤0.351.4

Missense OE?1.20 (1.10–1.31)

0≤0.61.4

Synonymous OE?0.95

0≤1.21.6

LoF obs/exp: 26 / 22.3Missense obs/exp: 364 / 303.2Syn Z: 0.43

Background carrier burden — how many people carry a rare variant somewhere in SLC22A9?

gnomAD v4 · ~731k individuals · PASS only

Rare means allele frequency under

Rare missense

1 in 49

806 rare PASS variants

Rare truncating (LoF)

1 in 560

135 rare PASS variants

Rare synonymous (reference)

1 in 120

281 rare PASS variants

Truncating variants are far rarer here than missense — that gap, in human units, is what constraint means for SLC22A9. 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 72	1 in 590
South Asian	~43k	1 in 45	1 in 270
Remaining (unassigned)	~30k	1 in 49	1 in 1,000
European (Finnish)	~27k	1 in 230	1 in 1,200
Admixed American	~22k	1 in 59	1 in 440
African / African American	~21k	1 in 57	1 in 490
East Asian	~20k	1 in 82	1 in 400
Ashkenazi Jewish	~13k	1 in 180	1 in 1,100
Middle Eastern	~2,884	1 in 60	≈ 1 in 960

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