A method for Junctional Epidermolysis Bullosa diagnostication in draft horses

Junctional Epidermolysis Bullosa (JEB) is an inherited disease which causes skin lesions in newborn foals and results in large areas of skin loss. The mutation responsible for the disease is a cytosine insertion in the LAMC2 gene, which results in absent expression of the laminin γ2 polypeptide chain of laminin 5. JEB is inherited as an autosomal recessive trait (Spirito et al. 2002, Milenkovic et al. 2003, Spirito et al. 2002). Our objective was to develop an easy and efficient method for correctly identifying the normal homozygous and heterozygous carrier horses for the JEB trait. We analyzed a population of Romanian Draft Horses using a set of primers which amplify a fragment from the LAMC2 gene possibly containing the insertion. The number of allele peaks depends on whether the horse tested is a heterozygote (carrier) or homozygote (normal or JEB affected). Results suggest that the genetic test will be useful in identifying horses which are heterozygous for the JEB trait and foals with JEB.