GMPPB
Chr 3ARGDP-mannose pyrophosphorylase B
Also known as: LGMDR19, MDDGA14, MDDGB14, MDDGC14
The protein catalyzes the conversion of mannose-1-phosphate and GTP to GDP-mannose, which is essential for N-linked oligosaccharide production. Biallelic mutations cause autosomal recessive muscular dystrophy-dystroglycanopathy with a spectrum ranging from severe congenital forms with brain and eye anomalies (type A) to milder limb-girdle presentations (type C). The pathogenic mechanism involves defective glycosylation of dystroglycan due to impaired GDP-mannose synthesis.
Definitive — sufficient evidence for diagnostic panels
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
Highly tolerant — LoF variants common in population
Mild missense constraint
ClinVar Variant Classifications
0 submitted variants in ClinVar
Protein Context — Lollipop Plot
GMPPB · protein map & ClinVar variants
Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.
3D Protein StructureAlphaFold
External Resources
Links to major genomics databases and tools
Clinical Trials
Active and recruiting trials from ClinicalTrials.gov
External Resources
Links to major genomics databases and tools