Intestinal cobalamin malabsorption Australian Shepherd type (IGS)
Intestinal cobalamin malabsorption Australian Shepherd type (IGS) is a hereditary disease affecting Australian Shepherds. 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 $ a mutation in a gene coding for amnionless occurs, a protein that together with cubilin 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 show as early as 8 weeks of age and include inappetence, failure to gain weight and failure to grow. Clinical recovery can be achieved with regular parenteral cobalamin supplementation.
Fyfe, J.C., Hemker, S.L., Venta, P.J., Fitzgerald, C.A., Outerbridge, C.A., Myers, S.L., and Giger, U. (2013). An exon 53 frameshift mutation in CUBN abrogates cubam function and causes Imerslund-Gräsbeck syndrome in dogs. Mol. Genet. Metab. 109, 390–396.
Owczarek-Lipska, M., Jagannathan, V., Drögemüller, C., Lutz, S., Glanemann, B., Leeb, T., and Kook, P.H. (2013). A frameshift mutation in the cubilin gene (CUBN) in Border Collies with Imerslund-Gräsbeck syndrome (selective cobalamin malabsorption). PLoS ONE 8, e61144.
Turnaround time: 15 business days