Glycogen branching enzyme deficiency, GBED

 

Gene: GBE1

Transmission: Autosomal

Mutation: Substitution, GBE1; c.102 C>A, exon1

Medical system: Metabolic

Breeds: Quarter Horse, Paint Horse and related breeds

Age of onset of symptoms: About 8 weeks of age

Glycogen Branching Enzyme Deficiency (GBED) is a genetic glycogen storage disease encountered in American Quarter Horse and related breeds.  The disease is caused by a deficiency of the GBE enzyme(Glycogen Branching Enzyme), which normally plays an important role in the use of energy and the mobilization of glycogen into glucose in the liver.  The disease can result in abortions and stillbirths.  Affected animals that survive after birth may have joint stiffness (arthrogryposis) originally caused by decreased fetal movement.  They also show signs of dysfunction in the heart, liver and skeletal muscles around 8 weeks of age.  Affected foals generally survive only a few months.

 

References:

OMIA link: [0420-9796]

Aleman M, Scalco, R, Malvick J, et al. (2022) Prevalence of genetic mutations in horses with muscle disease from a neuromuscular disease laboratory. J Equine Vet Sci 118:104129.  [pubmed/36150530]

lmodóvar-Payá A, Villarreal-Salazar M, de Luna N, et al. (2020) Preclinical research in glycogen storage diseases: A comprehensive review of current animal models. Int J Mol Sci 21:9621.  [pubmed/33348688]

Tyron RC, Penedo MC, McCue ME, et al. (2009) Evaluation of allele frequencies of inherited disease genes in subgroups of American Quarter Horses. JAVMA 234(1) :120-125. [pubmed/19119976]

Wagner ML, Valberg SJ, Ames EG, et al. (2006) Allele frequency and likely impact of the glycogen branching enzyme deficiency gene in Quarter Horse and Paint Horse populations. J Vet Intern Med. 20(5):1207-1211. [pubmed/17063718]

Ward TL, Valberg SJ, et al. (2004) Glycogen branching enzyme (GBE1) mutation causing équine glycogen Storage disease IV. Mammalian Genome 15 :570-577. [pubmed/15366377]