Post-weaning multisystemic wasting syndrome (PMWS) has spread dramatically among pigs over the last years with devastating consequences for animal welfare and great economic losses for farmers. Porcine circovirus 2 (PCV2) is the necessary causal infectious agent of PMWS, but other factors are needed for full development of the disease. Among such factors genetics or breed of pigs have been speculated to play a role and by now several studies have confirmed that breed or boar line is of importance.
A linkage study in 14 litters, lead us to the hypothesis that a locus in a region close to microsatellite markers KVL3525 and KVL3526 on porcine chromosome 13 is associated with PMWS development. This was subsequently confirmed by an association study in which KVL3525 was found to be associated with development of PMWS. KVL3525 is located in the middle of the MyRIP gene. This gene encodes a protein involved in transport of vesicles in the cytosol. It is an interesting candidate gene because a number of studies have shown that impaired transport and accumulation of PCV2 in cells of the innate immune system may be an important factor in PMWS pathogenesis. We sequenced MyRIP in PMWS affected and unaffected pigs and identified several single nucleotide polymorphisms (SNPs). However, none of the SNPs were associated with PMWS status.