|Tait Jr, R|
Submitted to: International Symposium of Animal Functional Genomics
Publication Type: Abstract Only
Publication Acceptance Date: 7/5/2011
Publication Date: 10/10/2011
Citation: Downey, E.D., Conrad, E.C., Lintz, K.K., Ridpath, J.F., Tait Jr, R.C., Garrick, D.J., Reecy, J.M. 2011. Whole genome analysis using Bayesian models to identify candidate genes for immune response to vaccination [abstract]. In: International Symposium on Animal Functional Genomics, October 10-12, 2011, Dublin, Ireland. p. 31. Interpretive Summary:
Technical Abstract: This study identified genome regions associated with variation in immune response to vaccination against bovine viral diarrhea virus type 2 (BVDV 2) in American Angus calves. Calves were born in the spring or fall of 2006-2008 (n = 620). Two doses of modified live vaccine were administered three weeks apart. Levels of viral neutralizing antibodies against BVDV2 in serum samples (VN titer) were determined based on the ability of antibodies to block cytopathic effect (CPE) in cultured cells infected with cytopathic BVDV2. VN titers, recorded as log base two reciprocal of the highest serum dilution that blocked CPE, were determined at initial vaccination and three weeks post-booster vaccination (final titer). Overall response was measured as the difference between final and initial titers. Statistical analysis indicated that initial titer levels were significantly (n = 611; p < 0.05; R**2 = 0.647) influenced by calf gender, year, season, birth weight, calf age, and age of dam. Overall response was significantly effected (p < 0.05; R**2 = 0.794) by initial titer quadratic, year by season interaction, wean stress timing, dam age, and pinkeye infection. Animals were genotyped using BovineSNP50 Infinium-beadchips. Simultaneous analysis of fixed effects with all SNPs were performed using GenSel Bayes-C, based on continuous trait model that treated SNP effects as random with an assumed fraction (pi = 0.999) having no effect. The posterior means for initial titer and overall response were 0.09 and 0.15, respectively. Visualization of large effect SNP locations indicates that there are candidate genes (BOLA-DQA1-5, BOLA-DQB) in close proximity to associated SNPs. While immune response appears lowly heritable, associated SNPs with the greatest effects are in the MHC region.