Genetic factors influencing major congenital anomalies in pigs

Although the incidence of congenital anomalies is quite low (around 1%), it is a significant problem in the pig industry. These defects have a serious impact on animal welfare and result in economic losses due to carcass depreciation. The most important congenital defects that occur in piglets are scrotal or inguinal hernias, cryptorchidism, and intersexuality. In 2006, it was declared a priority by BIOPORC (IFIP and the French pig breeding companies ADN, GENE+, Nucleus and Pen Ar Lan) and two research projects, ANOPORC (Ministère de l’Agriculture 2007‐2008) and SwAn (ANR 2009‐2012), were initiated in collaboration with INRA. The aim of this paper was to describe the phenotypic and molecular datasets, developed as part of the ANOPORC project, and to present some of the first findings from the efforts to identify genes underlying congenital anomalies (SwAn). Available molecular tools in swine enable large scale, genome wide association studies to identify chromosomal regions containing causal genes. A strong association signal has been identified between intersexuality and a small region located on chromosome 12. These results are just one example of the approach that will be used to identify genes involved in scrotal/inguinal hernias and cryptorchidism.