Is DRC1 p.Ser26Trp (c.77C>G) pathogenic?

DRC1 p.Ser26Trp (c.77C>G) is classified Uncertain significance in DRC1 (ClinVar, Single submitter, 1 submitter; last evaluated 2019-07-22). AlphaMissense: ambiguous (0.4639); Very rare (popmax 0.00266%, afr); Associated with primary ciliary dyskinesia.

What condition is associated with DRC1 p.Ser26Trp (c.77C>G)?

DRC1 p.Ser26Trp (c.77C>G) is associated with primary ciliary dyskinesia (ClinVar).

How common is DRC1 p.Ser26Trp (c.77C>G) in the general population?

DRC1 p.Ser26Trp (c.77C>G) is very rare (popmax 0.00266%, afr) (gnomAD).

How is Primary ciliary dyskinesia inherited?

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

What do computational predictors say about DRC1 p.Ser26Trp (c.77C>G)?

AlphaMissense predicts ambiguous (score 0.4639) — an in-silico prediction, not a clinical call.

DRC1 p.Ser26Trp

c.77C>G · rs745542616 · VCV643840

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

ambiguous

0.4639 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.00266%, afr)

Missense predictors

1/2 damaging

REVEL, SaProt · AlphaMissense no call

Conditions

primary ciliary dyskinesia

Computational evidence

Protein change
AlphaMissense	0.4639	ambiguous
REVEL	0.241	benign-leaning
SaProt	LLR -11.11	damaging
⇒ SaProt calls this damaging; REVEL does not; AlphaMissense makes no call.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 7.5	GERP 2.4, phastCons 1
Regional constraint	o/e 0.99	unconstrained · MANE · 55 kb · p 0.71 · regional, not allelic
Overall
CADD	25.9	PHRED · no single calibrated threshold — expert panels disagree

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

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00266% African / African-American · 2/75,050 alleles

Filtering AF 0.000442% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.000166%

Overall 0.000124% 2/1,613,368 alleles · very rare

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: DRC1
Protein: p.Ser26Trp
Coding: c.77C>G
MANE Select: NM_145038
dbSNP: rs745542616
Type: single nucleotide variant
Location: chr2:26402066 (GRCh38)
Gene constraint: LOEUF 0.867 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 75.44 · 1 PDB

Full DRC1 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

primary ciliary dyskinesia — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Primary ciliary dyskinesia (Orphanet):

Inheritance: Autosomal dominant, Autosomal recessive, X-linked recessive
Onset: Neonatal
Prevalence: 1-5 / 10 000 (Pakistan)

Similar variants

DRC1 p.Gln118Ter Pathogenic/Likely pathogenic ★★ same condition
DRC1 p.Gln337Ter Pathogenic/Likely pathogenic ★★ same condition
DRC1 p.Ser642Ter Pathogenic/Likely pathogenic ★★ same condition
DRC1 p.Ala250Val Uncertain significance ★★ ⚠ same condition
DRC1 p.Ala391Val Uncertain significance ★★ ⚠ same condition
DRC1 p.Ala416Gly Uncertain significance ★★ ⚠ same condition
DRC1 p.Ala45Val Uncertain significance ★★ ⚠ same condition
DRC1 p.Ala473Val Uncertain significance ★★ ⚠ 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/drc1-p-ser26trp (accessed [today's date]).

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