CSPP1 c.2241+18C>A
Likely benign
Single submitter
Classification
Likely benign
ClinVar
Review
Single submitter ★☆☆☆
ClinVar · 1 submitter
gnomAD v4.1
Rare
very rare (popmax 0.000254%, nfe)
Conditions
1
Joubert syndrome 21
Computational evidence
| Protein change | ||
| Missense predictors do not apply to this variant type; conservation carries the signal. | ||
| Splicing | ||
| Splice region | donor +18 | near-intronic (+18 nt from the splice site) |
|---|---|---|
| SpliceAI | — | not assessed · no allele here is in the release |
| Constraint at this position | ||
| Conservation | phyloP -1.2 | GERP -5.1 |
| Non-coding constraint | Z 2.23 | 1 kb window · o/e 0.84 · regional · uncalibrated |
| Overall | ||
| CADD | 7.676 | PHRED · no single calibrated threshold — expert panels disagree |
Population frequency
gnomAD v4.1 · exomes + genomes
Grpmax group
0.000254%
European (non-Finnish) · 2/786,262 alleles
Filtering AF
4.2e-05%
ClinGen BA1/BS1 input
FAF95, joint · FAF99 1.6e-05%
Overall
0.000195%
2/1,024,180 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
- CSPP1
- Coding
- c.2241+18C>A
- MANE Select
- NM_001382391
- Type
- single nucleotide variant
- Location
- chr8:67154154 (GRCh38)
- Gene constraint
- LOEUF 0.876 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
- Structure
- AlphaFold pLDDT 57.34
Similar variants
- CSPP1 c.1022+1G>T Likely pathogenic ★★ same condition
- CSPP1 c.1187+1G>A Pathogenic/Likely pathogenic ★★ same condition
- CSPP1 c.1497-2A>C Likely pathogenic ★★ same condition
- CSPP1 c.1697+1G>T Pathogenic/Likely pathogenic ★★ same condition
- CSPP1 c.2968+1G>A Pathogenic ★★ same condition
- CSPP1 c.2968+1G>T Pathogenic ★★ same condition
- CSPP1 c.923+1G>C Pathogenic ★★ same condition
- CSPP1 c.-69C>T Pathogenic/Likely 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/cspp1-c-2241-plus-18c-a (accessed [today's date]).
Preprint & method: sugi.bio/variant/method Machine-readable: this page as Markdown