C2CD3 c.1843+121C>A
Benign
Multiple submitters
Classification
Benign
ClinVar
Review
Multiple submitters ★★☆☆
ClinVar · 2 submitters
gnomAD v4.1
Common
common (popmax 20.9%, afr) — too common for a highly-penetrant pathogenic allele
Computational evidence
| Protein change | ||
| Missense predictors do not apply to this variant type; conservation carries the signal. | ||
| Splicing | ||
| Splice region | donor +121 | deep intronic (+121 nt into the intron) |
|---|---|---|
| SpliceAI | — | not assessed · no allele here is in the release |
| Constraint at this position | ||
| Conservation | phyloP -4.1 | GERP 0.12 |
| Overall | ||
| CADD | 0.086 | PHRED · no single calibrated threshold — expert panels disagree |
Population frequency
gnomAD v4.1 · exomes + genomes
Grpmax group
20.9%
African / African-American · 10,912/52,280 alleles
Filtering AF
20.5%
ClinGen BA1/BS1 input
FAF95, joint · FAF99 20.4%
Overall
2.82%
19,846/702,544 alleles · common
| Ancestry group | Frequency | 1 in |
|---|---|---|
| African / African-Americangrpmax | 20.9% | 5 |
| Remaining individualsnot grpmax-eligible | 2.62% | 38 |
| Ashkenazi Jewishnot grpmax-eligible | 2.13% | 47 |
| Finnishnot grpmax-eligible | 2.09% | 48 |
| Admixed American | 1.62% | 62 |
| East Asian | 1.39% | 72 |
| European (non-Finnish) | 1.32% | 76 |
| Middle Eastern | 0.868% | 115 |
| South Asian | 0.303% | 330 |
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
- C2CD3
- Coding
- c.1843+121C>A
- MANE Select
- NM_001286577
- dbSNP
- rs12291090
- Type
- single nucleotide variant
- Location
- chr11:74113659 (GRCh38)
- Gene constraint
- LOEUF 0.637 · pLI <0.01 (gnomAD)
- Structure
- AlphaFold pLDDT 55.65
Similar variants
- C2CD3 c.3911-2A>T Pathogenic/Likely pathogenic ★★ same type
- C2CD3 p.Arg621Ter Pathogenic/Likely pathogenic ★★ same type
- C2CD3 p.Arg666Ter Pathogenic ★★ same type
- C2CD3 p.Arg768Ter Pathogenic/Likely pathogenic ★★ same type
- C2CD3 p.Tyr173Ter Pathogenic/Likely pathogenic ★★ same type
- C2CD3 c.2085+5G>A Uncertain significance ★★ same type
- C2CD3 c.4951+6C>T Uncertain significance ★★ same type
- C2CD3 c.5495+4A>G 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/c2cd3-c-1843-plus-121c-a (accessed [today's date]).
Preprint & method: sugi.bio/variant/method Machine-readable: this page as Markdown