F8 p.Ser554Gly
c.1660A>G · rs137852419 · VCV10226
ClinGen expert panel — Coagulation Factor Deficiency VCEP
Pathogenic for hemophilia A. Applied ACMG criteria (verbatim):
PP4_Moderate PP1_Strong PS4_Very PP3
Curation rationale (ClinGen, verbatim)
The c.1660A>G (p.Ser554Gly) missense variant has a REVEL score of 0.938 which meets PP3 criteria (threshold >0.6). This variant is present in 1 hemizygote in gnomAD v2.1.1 and therefore, does not meet criteria for rarity in the population. Fifty-three patients are reported in Johnsen, et. al. 2107 with mild/moderate hemophilia A and the Gly554Ser variant, meeting F8 phenotype criteria for PS4_Very strong and PP4_Moderate (PMID: 29296726). The variant has been found to segregate with hemophilia A across 6 meioses among 4 different families, the PP1 criteria at the strong weight (Internal VCEP contributor). This variant has been reported in individuals who developed an inhibitor to factor replacement therapy and discrepant chromogenic and one-stage factor VIII activity levels (CDC CHAMPS database/Internal VCEP contributor). In summary, this variant meets criteria to be classified as pathogenic. ACMG/AMP criteria applied, as specified by the Coagulation Factor Deficiency Variant Curation Expert Panel for F8: PS4_Very strong, PP1_Strong, PP4_Moderate, PP3.
ClinGen Evidence Repository → · reported verbatim, not re-tallied by Sugi Variant.
Computational evidence
| Protein change | ||
| AlphaMissense | 0.5126 | ambiguous |
|---|---|---|
| REVEL | 0.938 | strongly pathogenic-leaning |
| SaProt | LLR -12.84 | damaging |
| ⇒ REVEL and SaProt both call this damaging; AlphaMissense is indeterminate. | ||
| Splicing | ||
| SpliceAI | — | not assessed · no allele here is in the release |
| Constraint at this position | ||
| Conservation | phyloP 7.7 | GERP 1.7, phastCons 1 |
| Regional constraint | o/e 0.74 | unconstrained · MANE · 38 kb · p 2.6e-06 · regional, not allelic |
| Overall | ||
| CADD | 23.8 | PHRED · no single calibrated threshold — expert panels disagree |
AlphaMissense carries the ACMG weight for missense; REVEL and SaProt are independent agreement signals.
Population frequency
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
- F8
- Protein
- p.Ser554Gly
- Coding
- c.1660A>G
- MANE Select
- NM_000132
- dbSNP
- rs137852419
- Type
- single nucleotide variant
- Location
- chrX:154957049 (GRCh38)
- Structure
- AlphaFold pLDDT 61.20 · 29 PDB
- Residue 554
- the plastocyanin-like 3 domain; a UniProt-annotated variant site (in hema; moderate); a UniProt-annotated variant site (in hema; mild); the f5/8 type a 2 domain
Disease context
hemophilia A — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatmentsFor Hemophilia A (Orphanet):
- Inheritance
- X-linked recessive
- Onset
- Childhood, Infancy, Neonatal
- Prevalence
- 1-9 / 100 000 (Worldwide)
Similar variants
- F8 c.6429+2T>A Pathogenic ★★★ same condition
- F8 p.Ala111Thr Likely pathogenic ★★★ same condition
- F8 p.Ala2220Pro Pathogenic ★★★ same condition
- F8 p.Ala415Asp Likely pathogenic ★★★ same condition
- F8 p.Ala415Val Pathogenic ★★★ ⚠ same condition
- F8 p.Arg1768His Pathogenic ★★★ ⚠ same condition
- F8 p.Arg1800His Pathogenic ★★★ same condition
- F8 p.Arg2016Trp 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/f8-p-ser554gly (accessed [today's date]).
Preprint & method: sugi.bio/variant/method Machine-readable: this page as Markdown