myopathy caused by variation in GMPPB

Summary

myopathy caused by variation in GMPPB (MONDO:0700084) is a disease caused by GMPPB (GenCC Strong), with 1 cohort gene.

At a glance

• Causal gene: GMPPB (GenCC Strong)
• Cohort genes: 1
• ClinVar variants: 1

Clinical features

No curated clinical features (Orphanet) for this disease.

Identifiers

Disease identifiers

Field	Value
Canonical name	myopathy caused by variation in GMPPB
Mondo ID	MONDO:0700084
GARD	0026352
Is cancer (heuristic)	no

Also known as: GMPPB-related myopathy · myopathy caused by mutation in GMPPB

Data availability: 1 ClinVar variant · 1 GenCC gene-disease record.

Disease family

An umbrella term covering 3 Mondo subtypes.

Classification path: disease › human disease › disease by body system or component › musculoskeletal system disorder › muscle tissue disorder › skeletal muscle disorder › myopathy › myopathy caused by variation in GMPPB

Related subtypes (31): polyglucosan body myopathy, muscular atrophy, myopathy of extraocular muscle, acute quadriplegic myopathy, myofascial pain syndrome, myopathy with abnormal lipid metabolism, proximal myopathy with focal depletion of mitochondria, Brody myopathy, rippling muscle disease, myopathy due to myoadenylate deaminase deficiency, proximal myopathy with extrapyramidal signs, intermediate nemaline myopathy, hereditary inclusion-body myopathy, hereditary continuous muscle fiber activity, congenital myopathy, muscular dystrophy, metabolic myopathy, myositis disease, collagen 6-related myopathy, myopathy caused by variation in CRPPA, drug-induced myopathy, myopathy caused by variation in FKRP, myopathy caused by variation in FKTN, myopathy caused by variation in POMGNT1, myopathy caused by variation in POMGNT2, myopathy caused by variation in POMT1, myopathy caused by variation in POMT2, FHL1-related myopathy, myopathy, sarcoplasmic body, myopathy with myalgia, increased serum creatine kinase, and with or without episodic rhabdomyolysis 2, myopathy with myalgia, increased serum creatine kinase, and with or without episodic rhabdomyolysis

Subtypes (3): muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A14, muscular dystrophy-dystroglycanopathy (congenital with intellectual disability), type B14, autosomal recessive limb-girdle muscular dystrophy type 2T

Genetics & variants

GWAS landscape

No GWAS associations recorded — common-variant (GWAS) studies don’t cover this disease (typical for Mendelian / rare diseases). See the curated gene cohort and Mendelian overlap below.

Variant details and genetic-evidence tiers

ClinVar germline variants

1 retrieved; paginated sample, class counts are floors:

1 likely pathogenic

ClinVar	Variant (HGVS)	Gene	Classification	Review
2500893	NM_021971.4(GMPPB):c.291_294del (p.Ser98fs)	GMPPB	Likely pathogenic	criteria provided, single submitter

Genes & proteins

Mendelian disease overlap and somatic drivers

GenCC: 12 · Orphanet: 5 · OMIM-shared: 0 · Dual-evidence (GWAS+Mendelian): 0

GenCC gene–disease validity (cohort genes)

the Disease column is the GenCC-asserted condition — a cohort gene’s strongest validity may be for a related predisposition syndrome.

Gene	Classification	Inheritance	Disease	Records
GMPPB	Strong	Autosomal recessive	myopathy caused by variation in GMPPB	12

Orphanet rare-disease linkage (cohort genes)

Gene	Orphanet ID	Rare disease
GMPPB	Orphanet:353327	Congenital myasthenic syndrome with glycosylation defect
GMPPB	Orphanet:363623	GMPPB-related limb-girdle muscular dystrophy R19
GMPPB	Orphanet:370959	Congenital muscular dystrophy with cerebellar involvement
GMPPB	Orphanet:370968	Congenital muscular dystrophy with intellectual disability
GMPPB	Orphanet:588	Muscle-eye-brain disease

Cohort genes → proteins

1 cohort genes, 1 distinct canonical proteins.

Evidence partition

Subset	Genes
multi_evidence	1

Cohort genes (full)

Symbol	HGNC	Ensembl	UniProt	Name	Evidence
GMPPB	HGNC:22932	ENSG00000173540	Q9Y5P6	Mannose-1-phosphate guanylyltransferase catalytic subunit beta	gencc,clinvar

Cohort function summary

Lead sentence per gene, UniProt-curated.

Symbol	Protein name	Function (lead sentence)
GMPPB	Mannose-1-phosphate guanylyltransferase catalytic subunit beta	Catalytic subunit of the GMPPA-GMPPB mannose-1-phosphate guanylyltransferase complex.

Protein-family classification

Druggable: 1 · Difficult: 0 · Unknown: 0 · Druggable fraction: 1.0

Family distribution

Cohort families vs a genome-wide background (hypergeometric, BH-FDR; fold = observed/expected). Counts kept; sorted by enrichment, so the catch-all Other/Unknown bucket no longer leads.

Family	Genes	Fold	FDR
Enzyme (other)	1	12.0×	0.083

Per-gene assignment

Symbol	Family	Druggable?	EC	InterPro (top 3)
GMPPB	Enzyme (other)	yes	2.7.7.13	NTP_transferase_dom, Hexapep_transf_CS, Nucleotide-diphossugar_trans

Expression context

Cohort genes with no expression data: 0.

1 cohort gene are a single-cell marker in ≥1 SCXA experiment.

Breadth distribution (Bgee present_calls)

Bucket	Genes
narrow (1-5 tissues)	0
moderate (6-20)	0
broad (>20)	1
unknown	0

Top tissues across cohort

Tissue	Cohort genes
adenohypophysis	1
body of pancreas	1
mucosa of transverse colon	1

Per-gene tissue summary (top 30)

Symbol	Bgee breadth	FANTOM5 breadth	SCXA	Top tissues
GMPPB	172	ubiquitous	marker	body of pancreas, adenohypophysis, mucosa of transverse colon

Protein interactions among cohort

Intra-cohort edges: 0.

Hub genes (top 10 by interactor count)

Symbol	Interactor count
GMPPB	2,559

Structural data

PDB: 1 · AlphaFold-only: 0 · No structure: 0

Cohort genes with PDB structures (top 30)

Symbol	UniProt	PDB entries
GMPPB	Q9Y5P6	3

Function

Pathway analysis

Distinct Reactome pathways touched by cohort: 1. Enrichment computed across 1 evidence-associated genes (1 with Reactome annotation).

Pathways by enrichment

Over-representation of cohort genes vs the genome-wide background (hypergeometric test, Benjamini-Hochberg FDR; fold = observed/expected over 1 annotated cohort genes). Counts and members are kept as ground-truth; sorted by enrichment.

Pathway	Cohort genes	Fold	FDR	Sample cohort genes
Synthesis of GDP-mannose	1	1903.3×	5e-04	GMPPB

GO biological processes by enrichment

Over-representation of cohort genes vs the genome-wide background (hypergeometric test, Benjamini-Hochberg FDR; fold = observed/expected over 1 annotated cohort genes). Counts and members are kept as ground-truth; sorted by enrichment.

GO term	Cohort genes	Fold	FDR	Sample cohort genes
obsolete GDP-mannose biosynthetic process from mannose	1	5617.3×	4e-04	GMPPB
GDP-mannose biosynthetic process	1	2808.7×	4e-04	GMPPB
GDP-mannose metabolic process	1	2808.7×	4e-04	GMPPB

Therapeutics

Drug target analysis

Approved (phase 4): 0 · Phase ≥3: 0 · Phased (≥1): 0 · Undrugged: 1

Druggability breadth: 0 of 1 evidence-associated genes (0%) have a ChEMBL target (buckets above are over the deeply-mined display cohort).

Top cohort targets by molecule count

Symbol	Molecules	Max phase
GMPPB	0	0

Bioactivity and enzyme data

Enzyme cohort genes (≥1 EC): 1.

Cohort enzymes (BRENDA EC)

Symbol	EC numbers	Names
GMPPB	2.7.7.13	mannose-1-phosphate guanylyltransferase

Pharmacogenomics

Cohort genes with a PharmGKB record: 1; with CPIC/DPWG dosing guidelines: 0.

No cohort gene has a CPIC/DPWG genotype-guided dosing guideline (PharmGKB).

Chemical tractability of cohort targets

0 approved/phased compounds have measured bioactivity against a cohort gene (and aren’t yet in disease-level trials). This is a research / tractability signal, NOT a therapeutic recommendation — a bioactivity row often reflects off-target or screening binding (e.g. promiscuous kinase inhibitors against a cohort kinase), implying no disease mechanism.

Druggability pyramid

Cohort genes binned by druggability tier (high → low):

Tier	Definition	Genes	Symbols
A	Approved (phase 4 drug)	0
B	Phased (≥1) drug, not yet approved	0
C	Druggable family + PDB, no drug	1	GMPPB
D	Druggable family + AlphaFold only, no drug	0
E	Difficult family or no structure, no drug	0

Undrugged target profiles

1 cohort genes are undrugged. Ranked by ‘starting-point quality’ (assay depth + drugged-partner adjacency).

Symbol	ChEMBL assays	Drugged partners (top 3)
GMPPB	0	—

Clinical trials & evidence

Clinical trials

Clinical trials: 0.