A novel 12 bp deletion in the ITGB5 gene is strongly associated with Escherichia coli F4ac adhesion and increased susceptibility to infection in pigs

The bacterial strain enterotoxigenic Escherichia coli (ETEC) expressing F4 fimbriae is the major pathogen causing potentially fatal diarrhoea in neonatal and recently-weaned piglets. Our previously published results from a genome wide association study (GWAS) of the pig genome identified a promising candidate gene (ITGB5) for predicting the susceptibility to ETEC F4ab/ac infection, the gene encoding the integrin beta 5 (ITGB5) receptor. We report here the assembly and cloning of the complete porcine ITGB5 gene based on the latest reference sequence for swine, as well as our results following analysis of the coding regions of ITGB5 from a sample of pigs that included both resistant and susceptible animals. We identified a novel 12 bp deletion in the 5' UTR region of the gene that correlates perfectly with increased ETEC F4ac adhesion in pig gut epithelial cells, in sample of 335 pigs from 3 different breeds. These results indicate that the ITGB5 gene is an important adhesion molecule for E. coli F4ac, and that the 12 bp deletion could serve as a genetic marker for selecting against susceptible pigs in breeding programs. (C) 2014 Published by Elsevier B.V.