Is CCN6 p.Ser39Ter (c.116C>A) pathogenic?

CCN6 p.Ser39Ter (c.116C>A) is classified Pathogenic in CCN6 (ClinVar, Multiple submitters, 2 submitters; last evaluated 2025-10-05). Very rare (popmax 8.47e-05%, nfe); Associated with progressive pseudorheumatoid arthropathy of childhood.

What condition is associated with CCN6 p.Ser39Ter (c.116C>A)?

CCN6 p.Ser39Ter (c.116C>A) is associated with progressive pseudorheumatoid arthropathy of childhood (ClinVar).

How common is CCN6 p.Ser39Ter (c.116C>A) in the general population?

CCN6 p.Ser39Ter (c.116C>A) is very rare (popmax 8.47e-05%, nfe) (gnomAD).

How is Progressive pseudorheumatoid dysplasia inherited?

Typically Autosomal recessive (Orphanet). A genetic counselor can assess individual risk for a family.

CCN6 p.Ser39Ter

c.116C>A · rs2546919773 · VCV2965678

Pathogenic Multiple submitters

Classification

Pathogenic

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 2 submitters

Consequence

nonsense (stop-gain)

predicted LoF

gnomAD v4.1

Rare

very rare (popmax 8.47e-05%, nfe)

Conditions

progressive pseudorheumatoid arthropathy of childhood

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Consequence	nonsense (stop-gain)	predicted loss-of-function
NMD	predicted	premature termination codon in exon 2 of 5
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 1.3	GERP 0.056, phastCons 0.001
Overall
CADD	34.0	PHRED · no single calibrated threshold — expert panels disagree

Predicted loss-of-function is descriptive, not an applied PVS1 code.

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 8.47e-05% European (non-Finnish) · 1/1,180,018 alleles

Overall 6.2e-05% 1/1,614,140 alleles · very rare exomes 1/1,461,874 · genomes 0/152,266 · joint denominator

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: CCN6
Protein: p.Ser39Ter
Coding: c.116C>A
MANE Select: NM_198239
dbSNP: rs2546919773
Type: single nucleotide variant
Location: chr6:112061058 (GRCh38)
Gene constraint: LOEUF 1.055 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 74.30

Full CCN6 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

progressive pseudorheumatoid arthropathy of childhood — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Progressive pseudorheumatoid dysplasia (Orphanet):

Inheritance: Autosomal recessive
Onset: Childhood
Prevalence: 1-9 / 1 000 000 (Europe)

Similar variants

CCN6 p.Ser39= Likely benign ★ same residue
CCN6 c.49-1G>A Pathogenic/Likely pathogenic ★★ same condition
CCN6 c.590-1G>C Likely pathogenic ★★ same condition
CCN6 p.Ala197Pro Pathogenic/Likely pathogenic ★★ ⚠ same condition
CCN6 p.Cys223Gly Pathogenic ★★ same condition
CCN6 p.Cys337Tyr Pathogenic/Likely pathogenic ★★ same condition
CCN6 p.Cys52Ter Pathogenic/Likely pathogenic ★★ same condition
CCN6 p.Cys78Tyr 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/ccn6-p-ser39ter (accessed [today's date]).

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