C8A c.1603+20A>C
Likely benign
Single submitter
Classification
Likely benign
ClinVar
Review
Single submitter ★☆☆☆
ClinVar · 1 submitter
gnomAD v4.1
Rare
ultra-rare (popmax 0.0183%, amr)
Computational evidence
| Protein change | ||
| Missense predictors do not apply to this variant type; conservation carries the signal. | ||
| Splicing | ||
| Splice region | donor +20 | near-intronic (+20 nt from the splice site) |
|---|---|---|
| SpliceAI | — | not assessed · no allele here is in the release |
| Constraint at this position | ||
| Conservation | phyloP -2.3 | GERP -4 |
| Overall | ||
| CADD | 0.066 | PHRED · no single calibrated threshold — expert panels disagree |
Population frequency
gnomAD v4.1 · exomes + genomes
Grpmax group
0.0183%
Admixed American · 11/59,958 alleles
Filtering AF
0.0102%
ClinGen BA1/BS1 input
FAF95, joint · FAF99 0.00786%
Overall
0.000746%
12/1,608,324 alleles · ultra-rare
| Ancestry group | Frequency | 1 in |
|---|---|---|
| Admixed Americangrpmax | 0.0183% | 5,451 |
| Remaining individualsnot grpmax-eligible | 0.00161% | 62,252 |
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
- C8A
- Coding
- c.1603+20A>C
- MANE Select
- NM_000562
- dbSNP
- rs1345123380
- Type
- single nucleotide variant
- Location
- chr1:56912645 (GRCh38)
- Gene constraint
- LOEUF 1.168 · pLI <0.01 (gnomAD)
- Structure
- AlphaFold pLDDT 79.58 · 11 PDB
Similar variants
- C8A p.Arg424Ter Pathogenic ★★ same type
- C8A p.Arg498Ter Pathogenic/Likely pathogenic ★★ same type
- C8A p.Glu466Ter Pathogenic ★★ same type
- C8A p.Tyr210Ter Pathogenic/Likely pathogenic ★★ same type
- C8A p.Tyr384Ter Pathogenic/Likely pathogenic ★★ same type
- C8A p.Arg107Cys Uncertain significance ★★ ⚠ same type
- C8A p.Arg196His Uncertain significance ★★ ⚠ same type
- C8A p.Arg207Gln Uncertain significance ★★ ⚠ 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/c8a-c-1603-plus-20a-c (accessed [today's date]).
Preprint & method: sugi.bio/variant/method Machine-readable: this page as Markdown