Is CSPP1 p.Arg921= (c.2763T>C) pathogenic?

CSPP1 p.Arg921= (c.2763T>C) is classified Likely benign in CSPP1 (ClinVar, Single submitter, 1 submitter; last evaluated 2026-01-21). Absent from gnomAD v4.1; Associated with Joubert syndrome 21.

What condition is associated with CSPP1 p.Arg921= (c.2763T>C)?

CSPP1 p.Arg921= (c.2763T>C) is associated with Joubert syndrome 21 (ClinVar).

How common is CSPP1 p.Arg921= (c.2763T>C) in the general population?

CSPP1 p.Arg921= (c.2763T>C) is absent from gnomAD v4.1 (gnomAD).

CSPP1 p.Arg921=

c.2763T>C · rs2129562840 · VCV1624538

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Not reported

no allele count reported in gnomAD v4.1 (AN 1,607,438)

Conditions

Joubert syndrome 21

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP -1.4	GERP -5.2, phastCons 0.001
Overall
CADD	5.877	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

No allele count reported in gnomAD v4.1 (AN 1,607,438). This is missing data, not an absence: the variant may or may not be present in gnomAD. Rarity (ACMG PM2) and BA1/BS1 cannot be assessed for it.

Variant & gene context

Gene: CSPP1
Protein: p.Arg921=
Coding: c.2763T>C
MANE Select: NM_001382391
dbSNP: rs2129562840
Type: single nucleotide variant
Location: chr8:67164443 (GRCh38)
Gene constraint: LOEUF 0.876 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 57.34
Residue 921: the 'disordered' region

Full CSPP1 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

Joubert syndrome 21 — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Similar variants

CSPP1 p.Arg921His Uncertain significance ★★ same residue
CSPP1 p.Arg921Cys Uncertain significance ★ same residue
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

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-p-arg921 (accessed [today's date]).

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