Is CTC1 p.Pro9Arg (c.26C>G) pathogenic?

CTC1 p.Pro9Arg (c.26C>G) is classified Uncertain significance in CTC1 (ClinVar, Single submitter, 1 submitter; last evaluated 2026-02-02). AlphaMissense: likely benign (0.0823); Very rare (popmax 0.000424%, nfe); Associated with dyskeratosis congenita.

What condition is associated with CTC1 p.Pro9Arg (c.26C>G)?

CTC1 p.Pro9Arg (c.26C>G) is associated with dyskeratosis congenita (ClinVar).

How common is CTC1 p.Pro9Arg (c.26C>G) in the general population?

CTC1 p.Pro9Arg (c.26C>G) is very rare (popmax 0.000424%, nfe) (gnomAD).

How is Dyskeratosis congenita inherited?

Typically Autosomal dominant, Autosomal recessive (Orphanet). A genetic counselor can assess individual risk for a family.

What do computational predictors say about CTC1 p.Pro9Arg (c.26C>G)?

AlphaMissense predicts likely benign (score 0.0823) — an in-silico prediction, not a clinical call.

CTC1 p.Pro9Arg

c.26C>G · rs377386669 · VCV1409462

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely benign

0.0823 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.000424%, nfe)

Missense predictors

0/3 damaging

AlphaMissense, REVEL, SaProt

Conditions

dyskeratosis congenita

⚠ Built without this gene's context — gene constraint and dosage, protein structure, pathways, panels and related-variant links were not looked up for this page. why

Computational evidence

Protein change
AlphaMissense	0.0823	likely benign
REVEL	0.215	benign-leaning
SaProt	LLR -5.57	tolerated
⇒ AlphaMissense, REVEL and SaProt all call this tolerated.
Splicing
SpliceAI	—	not looked up on this page · why
Constraint at this position
Conservation	phyloP 0.036	GERP -4
Regional constraint	o/e 0.96	unconstrained · MANE · 20 kb · p 0.088 · regional, not allelic
Overall
CADD	15.67	PHRED · no single calibrated threshold — expert panels disagree

ClinVar classifies this uncertain; the computational predictors unanimously lean tolerated — a triage signal, not a reclassification

AlphaMissense carries the ACMG weight for missense; REVEL and SaProt are independent agreement signals.

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.000424% European (non-Finnish) · 5/1,178,708 alleles

Filtering AF 0.000124% ClinGen BA1/BS1 input FAF95, joint · FAF99 9e-05%

Overall 0.00031% 5/1,610,776 alleles · very rare exomes 4/1,458,614 · genomes 1/152,162 · 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: CTC1
Protein: p.Pro9Arg
Coding: c.26C>G
MANE Select: NM_025099
dbSNP: rs377386669
Type: single nucleotide variant
Location: chr17:8248011 (GRCh38)

Full CTC1 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

dyskeratosis congenita — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Dyskeratosis congenita (Orphanet):

Inheritance: Autosomal dominant, Autosomal recessive, X-linked recessive
Onset: Adolescent, Adult, Childhood, Infancy, Neonatal
Prevalence: 1-9 / 1 000 000 (Europe)

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/ctc1-p-pro9arg (accessed [today's date]).

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