Is CHST3 p.Gln91Ter (c.271C>T) pathogenic?

CHST3 p.Gln91Ter (c.271C>T) is classified Pathogenic in CHST3 (ClinVar, Single submitter, 1 submitter; last evaluated 2025-10-20). Very rare (popmax 0.00267%, afr); Associated with spondyloepiphyseal dysplasia with congenital joint dislocations.

What condition is associated with CHST3 p.Gln91Ter (c.271C>T)?

CHST3 p.Gln91Ter (c.271C>T) is associated with spondyloepiphyseal dysplasia with congenital joint dislocations (ClinVar).

How common is CHST3 p.Gln91Ter (c.271C>T) in the general population?

CHST3 p.Gln91Ter (c.271C>T) is very rare (popmax 0.00267%, afr) (gnomAD).

How is CHST3-related skeletal dysplasia inherited?

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

CHST3 p.Gln91Ter

c.271C>T · rs756133268 · VCV1445618

Pathogenic Single submitter

Classification

Pathogenic

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

Consequence

nonsense (stop-gain)

predicted LoF

gnomAD v4.1

Rare

very rare (popmax 0.00267%, afr)

Conditions

spondyloepiphyseal dysplasia with congenital joint dislocations

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	escapes	premature termination codon in the last exon (3 of 3) — the truncated protein is likely expressed. PVS1 input, not an applied code
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 4.9	GERP 0.67, phastCons 1
Overall
CADD	35.0	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 0.00267% African / African-American · 2/74,952 alleles

Filtering AF 0.0005% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.000366%

Overall 0.000806% 13/1,613,408 alleles · very rare

Ancestry group	Frequency	1 in
African / African-Americangrpmax	0.00267%	37,476
European (non-Finnish)	0.000932%	107,250

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: CHST3
Protein: p.Gln91Ter
Coding: c.271C>T
MANE Select: NM_004273
dbSNP: rs756133268
Type: single nucleotide variant
Location: chr10:72007302 (GRCh38)
Gene constraint: LOEUF 1.119 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 80.58

Full CHST3 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

spondyloepiphyseal dysplasia with congenital joint dislocations — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For CHST3-related skeletal dysplasia (Orphanet):

Inheritance: Autosomal recessive
Onset: Antenatal, Neonatal

Similar variants

CHST3 p.Arg221Cys Pathogenic/Likely pathogenic ★★ same condition
CHST3 p.Glu230Ter Pathogenic/Likely pathogenic ★★ same condition
CHST3 p.Phe159Ile Pathogenic/Likely pathogenic ★★ same condition
CHST3 c.*57G>T Uncertain significance ★★ same condition
CHST3 c.*66G>T Uncertain significance ★★ same condition
CHST3 p.Ala106Thr Uncertain significance ★★ ⚠ same condition
CHST3 p.Ala129Glu Uncertain significance ★★ ⚠ same condition
CHST3 p.Ala182Thr Uncertain significance ★★ ⚠ 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/chst3-p-gln91ter (accessed [today's date]).

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