Genetic diversity and disease resistance of horses exposed to Equine Infectious Anemia (EIA) in Argentina

DIAZ S; SADABA S; CORBI BOTTO C M; LIRON J P; LOPEZ R A; CARINO M H; VILLEGAS CASTAGNASSO E E; GIOVAMBATTISTA G; PERAL GARCIA P

Cairns

Congreso; 33rd Conference of the International Society of Animal Genetics; 2012

Society for Animal Genetics

A well registered history of survival of a group of horses exposed to the equine infectious anemia virus (EIA), gave rise to questions concerning their genetic composition as regards of the possible resistance to the disease. For this purpose, whole blood samples were retrieved from 50 horses residing in Chaco province, Argentina, and fractionated for biochemical, serological and molecular analysis. EIA serological condition was assessed by the Coggins?s test, and re-sampling of the same horses were performed in 3 different occasions throughout 2 years. Only 4 horses became seropositive during the time of the investigation, and no evidence of EIA acute infection or clinical symptoms were observed. DNA was isolated from whole blood and 15 molecular markers comprising horse STRs (ISAG panel), single nucleotide polymorphisms (SNPs) from candidate cytokines and the equine lymphocyte antigen (ELA), were typed by PCR-multiplex, PCR-Pyrosequencing and direct DNA sequencing methodologies. Population ge- netic analysis allowed describing the genetic profle of the horse sample, and polymorphic immune markers revealed elevated levels of polymorphism. To preliminary investigate the association to the EIA epidemiological condition, candidate cytokines SNPs (TNF-α, IL-12) and MHC class II alleles (DRA, DRB) were evaluated by odds ratio calculation, and values from 1.7 to 3.30 for some alleles, suggests that some polymorphisms of the cytokines and antigen presenting molecules could be related to the virus capability of infection and/or later immune response stages concerning the disease progression.