Is KIT p.Thr303= (c.909A>G) pathogenic?

KIT p.Thr303= (c.909A>G) is classified Likely benign in KIT (ClinVar, Multiple submitters, 2 submitters; last evaluated 2022-11-13). Very rare (popmax 0.00266%, afr); Associated with hereditary neoplastic syndrome.

What condition is associated with KIT p.Thr303= (c.909A>G)?

KIT p.Thr303= (c.909A>G) is associated with hereditary neoplastic syndrome, gastrointestinal stromal tumor (ClinVar).

How common is KIT p.Thr303= (c.909A>G) in the general population?

KIT p.Thr303= (c.909A>G) is very rare (popmax 0.00266%, afr) (gnomAD).

KIT p.Thr303=

c.909A>G · rs531740394 · VCV1765756

Likely benign Multiple submitters

Classification

Likely benign

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 2 submitters

gnomAD v4.1

Rare

very rare (popmax 0.00266%, afr)

Conditions

hereditary neoplastic syndrome

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Splicing
SpliceAI	<0.2	no splice effect predicted · four deltas, not one · how we know
Constraint at this position
Conservation	phyloP 2.1	GERP -2, phastCons 1
Overall
CADD	6.308	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00266% African / African-American · 2/75,050 alleles

Filtering AF 0.000442% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.000166%

Overall 0.000124% 2/1,613,652 alleles · very rare exomes 2/1,461,310 · genomes 0/152,342 · joint denominator

Rarity supports pathogenicity (ACMG PM2); frequency above a disease-specific BA1/BS1 threshold argues against it. A variant frequent in one ancestry group can be near-absent in others, so a single global figure can mislead.

Variant & gene context

Gene: KIT
Protein: p.Thr303=
Coding: c.909A>G
MANE Select: NM_000222
dbSNP: rs531740394
Type: single nucleotide variant
Location: chr4:54703876 (GRCh38)
Gene constraint: LOEUF 0.24 · pLI 1.00 · ClinGen HI 3/3 (gnomAD)
Structure: AlphaFold pLDDT 78.52 · 65 PDB
Residue 303: a β-strand; the ig-like c2-type 3 domain

Full KIT gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

hereditary neoplastic syndrome — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Also linked: gastrointestinal stromal tumor

Similar variants

KIT p.Thr303Ile Uncertain significance ★ ⚠ same residue
KIT p.Ala621Thr Pathogenic/Likely pathogenic ★★ same condition
KIT p.Asp820Tyr Pathogenic ★★ same condition
KIT p.Gln190Ter Pathogenic ★★ same condition
KIT p.Leu576Pro Pathogenic/Likely pathogenic ★★ same condition
KIT p.Lys642Glu Pathogenic ★★ same condition
KIT p.Trp557Arg Pathogenic/Likely pathogenic ★★ same condition
KIT p.Val559Ala Pathogenic/Likely pathogenic ★★ same condition

Built on 18 open, versioned datasets — ClinVar, gnomAD, AlphaMissense, REVEL, ClinGen & more — plus Sugi Variant's own cross-source analysis. Source data 2026-01–2026-10, ClinVar 2026-10. Full sources & versions →

Cite Sugi Variant

Gür T. Sugi Variant: A Deterministic Per-Variant Germline Reference from a Knowledge Graph for Humans and AI Agents. 2026. doi:10.5281/zenodo.21509445. This variant: https://sugi.bio/variant/kit-p-thr303 (accessed [today's date]).

Preprint & method: sugi.bio/variant/method Machine-readable: this page as Markdown