Is MPL p.Asp307= (c.921C>T) pathogenic?

MPL p.Asp307= (c.921C>T) is classified Likely benign in MPL (ClinVar, Single submitter, 1 submitter; last evaluated 2025-10-21). Very rare (popmax 0.00167%, amr); Associated with congenital amegakaryocytic thrombocytopenia.

How common is MPL p.Asp307= (c.921C>T) in the general population?

MPL p.Asp307= (c.921C>T) is very rare (popmax 0.00167%, amr) (gnomAD).

MPL p.Asp307=

Q: What condition is associated with MPL p.Asp307= (c.921C>T)?

MPL p.Asp307= (c.921C>T) is associated with congenital amegakaryocytic thrombocytopenia, essential thrombocythemia (ClinVar).

c.921C>T · rs764243911 · VCV1127487

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Rare

very rare (popmax 0.00167%, amr)

Conditions

congenital amegakaryocytic thrombocytopenia

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 -0.35	GERP -0.047
Overall
CADD	4.523	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00167% Admixed American · 1/60,016 alleles

Overall 0.000137% 2/1,461,882 alleles · very rare

Ancestry group	Frequency	1 in
Admixed Americangrpmax	0.00167%	60,016
Remaining individualsnot grpmax-eligible	0.0016%	62,506

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: MPL
Protein: p.Asp307=
Coding: c.921C>T
MANE Select: NM_005373
dbSNP: rs764243911
Type: single nucleotide variant
Location: chr1:43340454 (GRCh38)
Gene constraint: LOEUF 1.022 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 73.44 · 1 PDB

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

Disease context

congenital amegakaryocytic thrombocytopenia — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Also linked: essential thrombocythemia

Similar variants

MPL p.Asp307Glu Uncertain significance ★ ⚠ same residue
MPL c.1165+1G>C Likely pathogenic ★★ same condition
MPL c.1166-1G>C Likely pathogenic ★★ same condition
MPL c.1468+2T>C Pathogenic/Likely pathogenic ★★ same condition
MPL c.1469-2A>T Pathogenic/Likely pathogenic ★★ same condition
MPL c.1566-1G>A Likely pathogenic ★★ same condition
MPL c.1653+1G>C Likely pathogenic ★★ same condition
MPL c.79+2T>A 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/mpl-p-asp307 (accessed [today's date]).

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