Major histocompatibility complex (MHC) related cDNA probes associated withantibody response in meat-type chickens

The major histocompatibility complex (MHC) region was examined as a set of candidate genes for association between DNA markers and antibody response. Intercross F-2, families of chickens were generated from a cross between hi gh (HC) and low (LC) Escherichia coli(i) antibody lines. Restriction fragme nt length polymorphism (RFLP) analysis was conducted by using three MHC-rel ated cDNA probes: chicken MHC class IV (B-G), chicken MHC class I (B-F), an d human MHC-linked Tap2. Association between RFLP bands and three antibody response traits (E, call, sheep red blood cells and Newcastle disease virus ) were determined by two methods: by statistically analyzing each band sepa rately and also by analyzing all bands obtained from the three probes by us ing multiple regression analysis to account for the multiple comparisons. T he MHC class IV probe was the highest in polymorphisms but had the lowest n umber of bands associated with antibody response. The MHC class I probe yie lded 15 polymorphic bands of which four exhibited association with antibody response traits. The Tapa probe yielded 20 different RFLP bands of which f ive were associated with antibody production. Some Tapa bands were associat ed with multiple antibody response traits. The multiband analysis of the th ree probes' bands revealed more significant effects than the analysis of ea ch band separately. This study illustrates the efficacy of using multiple M HC region probes as candidate markers for quantitative trait loci (QTLs) co ntrolling antibody response in chickens.