Is TTN p.Ala655= (c.1965C>T) pathogenic?

TTN p.Ala655= (c.1965C>T) is classified Likely benign in TTN (ClinVar, Multiple submitters, 2 submitters; last evaluated 2022-08-23). Ultra-rare (popmax 0.0242%, sas); Associated with Cardiovascular phenotype.

What condition is associated with TTN p.Ala655= (c.1965C>T)?

TTN p.Ala655= (c.1965C>T) is associated with Cardiovascular phenotype, dilated cardiomyopathy 1G, autosomal recessive limb-girdle muscular dystrophy type 2J (ClinVar).

How common is TTN p.Ala655= (c.1965C>T) in the general population?

TTN p.Ala655= (c.1965C>T) is ultra-rare (popmax 0.0242%, sas) (gnomAD).

TTN p.Ala655=

c.1965C>T · rs760757049 · VCV1633495

Likely benign Multiple submitters

Classification

Likely benign

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 2 submitters

gnomAD v4.1

Rare

ultra-rare (popmax 0.0242%, sas)

Conditions

Cardiovascular phenotype

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 5.9	GERP 2.3, phastCons 1
Overall
CADD	12.43	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.0242% South Asian · 22/91,060 alleles

Filtering AF 0.0163% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.0138%

Overall 0.00136% 22/1,613,392 alleles · ultra-rare exomes 22/1,461,208 · genomes 0/152,184 · 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: TTN
Protein: p.Ala655=
Coding: c.1965C>T
MANE Select: NM_001267550
dbSNP: rs760757049
Type: single nucleotide variant
Location: chr2:178789471 (GRCh38)
Gene constraint: LOEUF 0.479 · pLI <0.01 · ClinGen HI 2/3 (gnomAD)

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

Disease context

Cardiovascular phenotype — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Also linked: dilated cardiomyopathy 1G autosomal recessive limb-girdle muscular dystrophy type 2J

Similar variants

TTN p.Ala655Asp Uncertain significance ★★ same residue
TTN c.100171+1G>A Likely pathogenic ★★ same condition
TTN c.100766-1G>T Likely pathogenic ★★ same condition
TTN c.100766-2A>T Likely pathogenic ★★ same condition
TTN c.106375-2A>G Pathogenic/Likely pathogenic ★★ same condition
TTN c.106531+1G>A Pathogenic/Likely pathogenic ★★ same condition
TTN c.107224-1G>C Pathogenic/Likely pathogenic ★★ same condition
TTN c.107377+1G>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/ttn-p-ala655 (accessed [today's date]).

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