Is CYCS p.Asn55Ser (c.164A>G) pathogenic?

CYCS p.Asn55Ser (c.164A>G) is classified Uncertain significance in CYCS (ClinVar, Single submitter, 1 submitter; last evaluated 2024-02-14). AlphaMissense: likely benign (0.082); Very rare (popmax 0.00102%, nfe).

How common is CYCS p.Asn55Ser (c.164A>G) in the general population?

CYCS p.Asn55Ser (c.164A>G) is very rare (popmax 0.00102%, nfe) (gnomAD).

What do computational predictors say about CYCS p.Asn55Ser (c.164A>G)?

AlphaMissense predicts likely benign (score 0.082) — an in-silico prediction, not a clinical call.

CYCS p.Asn55Ser

c.164A>G · rs2535206619 · VCV2807086

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely benign

0.082 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.00102%, nfe)

Missense predictors

0/3 damaging

AlphaMissense, REVEL, SaProt

Computational evidence

Protein change
AlphaMissense	0.082	likely benign
REVEL	0.054	moderately benign-leaning
SaProt	LLR -8.04	tolerated
⇒ AlphaMissense, REVEL and SaProt all call this tolerated.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 1.8	GERP 0.49, phastCons 1
Regional constraint	o/e 0.69	unconstrained · MANE · 415 bp · p 0.00062 · regional, not allelic
Overall
CADD	16.49	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 0.00102% European (non-Finnish) · 12/1,180,052 alleles

Filtering AF 0.000542% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.000428%

Overall 0.000821% 12/1,461,886 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: CYCS
Protein: p.Asn55Ser
Coding: c.164A>G
MANE Select: NM_018947
dbSNP: rs2535206619
Type: single nucleotide variant
Location: chr7:25123956 (GRCh38)
Gene constraint: LOEUF 0.335 · pLI 0.98 (gnomAD)
Structure: AlphaFold pLDDT 97.95 · 13 PDB
Residue 55: an α-helix

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

Similar variants

CYCS p.Gly42Ser Likely pathogenic ★★ same type
CYCS p.Ala52Thr Uncertain significance ★★ ⚠ same type
CYCS p.Leu33Val Uncertain significance ★★ ⚠ same type
CYCS c.-6T>G Benign/Likely benign ★★ same type
CYCS p.Ala51= Likely benign ★★ same type
CYCS p.Ile59= Likely benign ★★ same type
CYCS p.Pro72= Likely benign ★★ same type
CYCS p.Ala97Asp Likely pathogenic ★ ⚠ same type

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/cycs-p-asn55ser (accessed [today's date]).

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