Is MITF p.Ala303= (c.909A>C) pathogenic?

MITF p.Ala303= (c.909A>C) is classified Likely benign in MITF (ClinVar, Single submitter, 1 submitter; last evaluated 2025-08-15). Very rare (popmax 0.00133%, afr); Associated with melanoma, cutaneous malignant, susceptibility to, 8.

What condition is associated with MITF p.Ala303= (c.909A>C)?

MITF p.Ala303= (c.909A>C) is associated with melanoma, cutaneous malignant, susceptibility to, 8, Tietz syndrome, Waardenburg syndrome type 2A (ClinVar).

How common is MITF p.Ala303= (c.909A>C) in the general population?

MITF p.Ala303= (c.909A>C) is very rare (popmax 0.00133%, afr) (gnomAD).

MITF p.Ala303=

c.909A>C · VCV4785881

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Rare

very rare (popmax 0.00133%, afr)

Conditions

melanoma, cutaneous malignant, susceptibility to, 8

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP -2.1	GERP -4.3
Overall
CADD	2.478	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00133% African / African-American · 1/74,926 alleles

Overall 6.2e-05% 1/1,613,588 alleles · very rare exomes 0/1,461,380 · genomes 1/152,208 · 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: MITF
Protein: p.Ala303=
Coding: c.909A>C
MANE Select: NM_001354604
Type: single nucleotide variant
Location: chr3:69951840 (GRCh38)
Gene constraint: LOEUF 0.482 · pLI 0.99 · ClinGen HI 3/3 (gnomAD)
Structure: AlphaFold pLDDT 62.25 · 12 PDB

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

Disease context

melanoma, cutaneous malignant, susceptibility to, 8 — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Also linked: Tietz syndrome Waardenburg syndrome type 2A

For MITF-related melanoma and renal cell carcinoma predisposition syndrome (Orphanet):

Onset: Adult, Elderly

Similar variants

MITF c.1031+1G>A Pathogenic ★★ same condition
MITF c.1179+1G>A Pathogenic ★★ same condition
MITF c.355-1062G>C Pathogenic/Likely pathogenic ★★ same condition
MITF c.880+1G>A Likely pathogenic ★★ same condition
MITF c.955+1G>A Likely pathogenic ★★ same condition
MITF c.956-1G>A Pathogenic ★★ same condition
MITF p.Arg217Ter Pathogenic/Likely pathogenic ★★ same condition
MITF p.Arg310Gly 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/mitf-p-ala303 (accessed [today's date]).

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