Is DNMT3A p.Ser7= (c.21C>T) pathogenic?

DNMT3A p.Ser7= (c.21C>T) is classified Likely benign in DNMT3A (ClinVar, Single submitter, 2 submitters; last evaluated 2024-02-08). Ultra-rare (popmax 0.0336%, amr); Associated with Tatton-Brown-Rahman overgrowth syndrome.

What condition is associated with DNMT3A p.Ser7= (c.21C>T)?

DNMT3A p.Ser7= (c.21C>T) is associated with Tatton-Brown-Rahman overgrowth syndrome (ClinVar).

How common is DNMT3A p.Ser7= (c.21C>T) in the general population?

DNMT3A p.Ser7= (c.21C>T) is ultra-rare (popmax 0.0336%, amr) (gnomAD).

DNMT3A p.Ser7=

c.21C>T · rs748936424 · VCV2801853

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 2 submitters

gnomAD v4.1

Rare

ultra-rare (popmax 0.0336%, amr)

Conditions

Tatton-Brown-Rahman overgrowth syndrome

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 1.2	GERP -0.56, phastCons 1
Overall
CADD	12.91	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.0336% Admixed American · 17/50,612 alleles

Filtering AF 0.0214% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.0175%

Overall 0.00297% 46/1,547,692 alleles · ultra-rare exomes 29/1,395,458 · genomes 17/152,234 · joint denominator

Ancestry group	Frequency	1 in
Admixed Americangrpmax	0.0336%	2,977
African / African-American	0.00682%	14,657
East Asian	0.00483%	20,706
European (non-Finnish)	0.00175%	57,282
Remaining individualsnot grpmax-eligible	0.00167%	59,820
South Asian	0.0012%	83,612

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: DNMT3A
Protein: p.Ser7=
Coding: c.21C>T
MANE Select: NM_022552
dbSNP: rs748936424
Type: single nucleotide variant
Location: chr2:25313964 (GRCh38)
Gene constraint: LOEUF 1.998 · pLI <0.01 · ClinGen HI 3/3 (gnomAD)
Structure: AlphaFold pLDDT 73.97 · 47 PDB
Residue 7: the 'disordered' region

Full DNMT3A gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

Tatton-Brown-Rahman overgrowth syndrome — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Similar variants

DNMT3A p.Ser7Gly Uncertain significance ★ ⚠ same residue
DNMT3A c.1667+1G>A Likely pathogenic ★★ same condition
DNMT3A c.1937-2A>G Pathogenic ★★ same condition
DNMT3A c.2478+1G>A Pathogenic/Likely pathogenic ★★ same condition
DNMT3A c.2479-1G>A Likely pathogenic ★★ same condition
DNMT3A p.Arg143Ter Pathogenic ★★ same condition
DNMT3A p.Arg320Ter Pathogenic/Likely pathogenic ★★ same condition
DNMT3A p.Arg598Ter 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/dnmt3a-p-ser7 (accessed [today's date]).

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