GALNS

Chr 16

galactosamine (N-acetyl)-6-sulfatase

Also known as: GALNAC6S, GAS, GalN6S, MPS4A

NCBI Gene: 2588ENSG00000141012UniProt: P34059

This gene encodes N-acetylgalactosamine-6-sulfatase which is a lysosomal exohydrolase required for the degradation of the glycosaminoglycans, keratan sulfate, and chondroitin 6-sulfate. Sequence alterations including point, missense and nonsense mutations, as well as those that affect splicing, result in a deficiency of this enzyme. Deficiencies of this enzyme lead to Morquio A syndrome, a lysosomal storage disorder. [provided by RefSeq, Jul 2008]

GeneReviewsResearchGenerating clinical summary…

Primary Disease Associations & Inheritance

UniProtMucopolysaccharidosis 4A

Clinical highlights

Gene-disease validity (ClinGen)
mucopolysaccharidosis type 4A · ARDefinitivesufficient evidence for diagnostic panels
Interpreting a novel variant
Loss of function is the curated mechanism (Gene2Phenotype), though the gene is not strongly LoF-constrained in the population — weigh truncating variants against that tolerance.Curated gene-level mechanism — a prior for triage, not a per-variant call.
0
Active trials
40
Pubs (1 yr)
—
P/LP submissions
—
P/LP missense
1.01
LOEUF
LOF
Mechanism· G2P
📖
GeneReview available — GALNS
Authoritative clinical overview · Recommended first read
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Some data sources returned errors (1)

omim: Error: OMIM fetch failed: 429

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

gnomAD
Tolerant — LoF & missense variants common in population
LoF Constraint?
1.01LOEUF
pLI 0.000
Z-score 1.51
OE 0.69 (0.48–1.01)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint?
-0.43Z-score
OE missense 1.07 (0.98–1.17)
324 obs / 302.7 exp
Tolerant

Tolerant to missense variation

Observed / Expected Ratios?
LoF OE?0.69 (0.48–1.01)
0≤0.351.4
Missense OE?1.07 (0.98–1.17)
0≤0.61.4
Synonymous OE?1.32
0≤1.21.6
LoF obs/exp: 19 / 27.5Missense obs/exp: 324 / 302.7Syn Z: -2.90

ClinVar Variant Classifications

0 submitted variants in ClinVar

ClinVar

Protein Context — Lollipop Plot

GALNS · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

ClinicalTrials.gov

No active trials found for this gene.

Search ClinicalTrials.gov →

External Resources

Links to major genomics databases and tools

Franklin by Genoox
AI-powered variant curation and clinical analysis
DECIPHER
Genomic variants and phenotypes in rare disease patients