POMT1

Chr 9AR

protein O-mannosyltransferase 1

Also known as: LGMD2K, LGMDR11, MDDGA1, MDDGB1, MDDGC1, RT

NCBI Gene: 10585 ENSG00000130714 UniProt: Q9Y6A1 OMIM: 607423

The protein encoded by POMT1 is an endoplasmic reticulum O-mannosyltransferase that functions with POMT2 to glycosylate dystroglycan, which is essential for muscle and brain development. Autosomal recessive mutations cause a spectrum of dystroglycanopathies ranging from severe Walker-Warburg syndrome with brain and eye malformations to milder limb-girdle muscular dystrophy. The pathogenic mechanism involves defective glycosylation of alpha-dystroglycan, disrupting its binding to extracellular matrix proteins.

OMIM ResearchSummary from RefSeq, OMIM, UniProt

The protein encoded by this gene is an O-mannosyltransferase that requires interaction with the product of the POMT2 gene for enzymatic function. The encoded protein is found in the membrane of the endoplasmic reticulum. Defects in this gene are a cause of Walker-Warburg syndrome (WWS) and limb-girdle muscular dystrophy type 2K (LGMD2K). Several transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Oct 2008]

OMIM ResearchGenerating clinical summary…

Primary Disease Associations & Inheritance

Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A, 1MIM #236670

Muscular dystrophy-dystroglycanopathy (congenital with impaired intellectual development), type B, 1MIM #613155

Muscular dystrophy-dystroglycanopathy (limb-girdle), type C, 1MIM #609308

Clinical highlights

Gene-disease validity (ClinGen)

myopathy caused by variation in POMT1 · 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.

Active trials

Pubs (1 yr)

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P/LP submissions

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P/LP missense

0.93

LOEUF

LOF

Mechanism· G2P