Is TSC2 p.Pro1256= (c.3768G>A) pathogenic?

TSC2 p.Pro1256= (c.3768G>A) is classified Conflicting classifications of pathogenicity in TSC2 (ClinVar, Conflicting submitters, 11 submitters; last evaluated 2026-01-05). Ultra-rare (popmax 0.0504%, mid); Associated with hereditary neoplastic syndrome.

What condition is associated with TSC2 p.Pro1256= (c.3768G>A)?

TSC2 p.Pro1256= (c.3768G>A) is associated with hereditary neoplastic syndrome, tuberous sclerosis, tuberous sclerosis 2 (ClinVar).

How common is TSC2 p.Pro1256= (c.3768G>A) in the general population?

TSC2 p.Pro1256= (c.3768G>A) is ultra-rare (popmax 0.0504%, mid) (gnomAD).

TSC2 p.Pro1256=

c.3768G>A · rs201599540 · VCV281623

Conflicting classifications of pathogenicity Conflicting submitters

Classification

Conflicting classifications of pathogenicity

ClinVar

Review

Conflicting submitters ★☆☆☆

ClinVar · 11 submitters

gnomAD v4.1

Rare

ultra-rare (popmax 0.0504%, mid)

Conditions

hereditary neoplastic 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 -14	GERP -3.2
Overall
CADD	0.009	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.0504% Middle Eastern · 3/5,956 alleles

Filtering AF 0.0136% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00779%

Overall 0.00428% 69/1,612,824 alleles · ultra-rare

Ancestry group	Frequency	1 in
Middle Easterngrpmax	0.0504%	1,985
East Asian	0.0201%	4,987
Remaining individualsnot grpmax-eligible	0.008%	12,494
European (non-Finnish)	0.00407%	24,583
South Asian	0.0022%	45,536
Admixed American	0.00167%	60,028
African / African-American	0.00133%	75,062

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: TSC2
Protein: p.Pro1256=
Coding: c.3768G>A
MANE Select: NM_000548
dbSNP: rs201599540
Type: single nucleotide variant
Location: chr16:2081752 (GRCh38)
Gene constraint: LOEUF 0.203 · pLI 1.00 · ClinGen HI 3/3 (gnomAD)
Structure: AlphaFold pLDDT 68.81 · 2 PDB

Full TSC2 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: tuberous sclerosis tuberous sclerosis 2

Similar variants

TSC2 p.Pro1256Leu Uncertain significance ★★ ⚠ same residue
TSC2 c.1257+1G>A Pathogenic ★★ same condition
TSC2 c.1258-2A>G Pathogenic ★★ same condition
TSC2 c.1361+1G>A Pathogenic/Likely pathogenic ★★ same condition
TSC2 c.1361+1G>T Pathogenic/Likely pathogenic ★★ same condition
TSC2 c.1362-1G>A Pathogenic ★★ same condition
TSC2 c.138+2T>C Pathogenic ★★ same condition
TSC2 c.138+5G>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/tsc2-p-pro1256 (accessed [today's date]).

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