title: Mapping quantitative trait loci for T lymphocyte subpopulations in peripheral blood in swine.
abstract: BACKGROUND
  Increased disease resistance through improved general immune capacity would be beneficial for the welfare and productivity of farm animals. T lymphocyte subpopulations in peripheral blood play an important role in immune capacity and disease resistance in animals. However, very little research to date has focused on quantitative trait loci (QTL) for T lymphocyte subpopulations in peripheral blood in swine.
  
  
  RESULTS
  In the study, experimental animals consist of 446 piglets from three different breed populations. To identify QTL for T lymphocyte subpopulations in peripheral blood in swine, the proportions of CD4+, CD8+, CD4+CD8+, CD4+CD8-, CD4-CD8+, and CD4-CD8- T cells and the ratio of CD4+:CD8+ T cells were measured for all individuals before and after challenge with modified live CSF (classical swine fever) vaccine. Based on the combined data of individuals from three breed populations, genome-wide scanning of QTL for these traits was performed based on a variance component model, and the genome wide significance level for declaring QTL was determined via permutation tests as well as FDR (false discovery rate) correction. A total of 27 QTL (two for CD4+CD8+, one for CD4+CD8-, three for CD4-CD8+, two for CD4-CD8-, nine for CD4+, two for CD8+, and eight for CD4+:CD8+ ratio) were identified with significance level of FDR < 0.10, of which 11 were significant at the level of FDR < 0.05, including the five significant at FDR < 0.01.
  
  
  CONCLUSIONS
  Within these QTL regions, a number of known genes having potential relationships with the studied traits may serve as candidate genes for these traits. Our findings herein are helpful for identification of the causal genes underlying these immune-related trait and selection for immune capacity of individuals in swine breeding in the future.
authors.affiliation: Key Laboratory of Animal Genetics Breeding and Reproduction, Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Lu
authors.forename: Jian-Feng
authors.initials: JF
authors.lastname: Liu
authors.forename: Yuan-Fang
authors.initials: YF
authors.lastname: Gong
authors.forename: Zhi-Peng
authors.initials: ZP
authors.lastname: Wang
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.forename: Qin
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D000818:Animals; D006691:Classical Swine Fever / Q000235:genetics / Q000276:immunology; D060467:Disease Resistance / Q000235:genetics*; D016131:Lymphocyte Subsets / Q000276:immunology*; D040641:Quantitative Trait Loci; D013552:Swine / Q000235:genetics*; D013601:T-Lymphocytes / Q000276:immunology*