Intestinal cobalamin malabsorption Beagle Type (IGS)
Intestinal cobalamin malabsorption Beagle Type (IGS) is a hereditiray disorder affecting Beagles. Cobalamin, known as vitamin B12, plays an important role in many metabolic and synthesis pathways. Animals, as well as other higher organisms, are unable to synthesize cobalamin and need to obtain it by dietary intake. The uptake of dietary cobalamin requires several endogenous proteins. In Beagles a mutation in a gene coding for cubilin occurs, a protein that together with amnionless protein constitutes a receptor for cobalamin-GIF complex. Mutation leads to cobalamin malabsorption which results in low levels of serum cobalamin, hyperhomocysteinemia and methylmalonic aciduria. Clinical signs include lethargy, inappetence, failure to gain weight and failure to grow, macrocytosis and neutropenia. In cobalamin-deficient Beagles a degenerative liver disease develops. Clinical recovery can be achieved with regular parenteral cobalamin supplementation. The carrier frequency is 9%.
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