Posted at 23:07h
Niels C. Pedersen,DVM, PhD; Director Center for Companion Animal Health, University of California, Davis, CA
Over 100 published articles have appeared in the world’s literature concerning FIP since my extensive review of FIP in 2009 (1). The following is a summary of significant findings from a portion of these published works.
Origin of FIPV (the FECV to FIPV mutation)
The debate over the origins of the FIP virus (FIPV) continues to some degree, but there is no doubt that FIPV arises as a mutant of the ubiquitous feline enteric coronavirus (FECV). Although FIPVs are virtually identical genetically to FECVs within the same environment (2-4), FIP causing mutations are nonetheless unique to each cat (2,3,5,16). The nature of the mutations that cause an FECV to change to an FIPV has been the topic of several recent publications. The 3c accessory gene mutations were the first to be implicated in FECV-to-FIPV conversion (reviewed 1) and these findings have been corroborated by additional studies (2,3). However, a group from the University of Utrecht, after sequencing the complete genomes of a large number of FIPVs and FECVs, found a second mutation that occurred only in FIPVs (5). This mutation consisted of one or more single nucleotide polymorphisms (SNPs) in the fusion domain of the spike (S) gene that caused minor (synonymous) changes in single amino acids within this region.