title: Identification of Rfp-Y (Mhc-like) haplotypes in chickens of Cornell lines N and P.
abstract: Two strains of chickens selected for differential Marek's disease (MD) resistance or susceptibility were studied for the presence of the recently described Rfp-Y major histocompatibility complex (Mhc-like) haplotypes. MD resistant chickens from line N were fixed for the classical Mhc B21 haplotype, whereas MD susceptible line P chickens were fixed for the B19 haplotype. The Rfp-Y haplotypes were identified by restriction fragment polymorphism (RFP) analysis using enzymes and Mhc probes for B-G, B-L beta II, and B-FIV. In addition an Rfp-L beta III clone was developed that differentiated Rfp-L beta from B-L beta genes. Three Rfp-Y haplotypes, defined for both class I and class II Mhc-like loci, were identified in line N (Rfp-Y5, Rfp-Y7, and Rfp-Y8) and in line P (Rfp-Y5, Rfp-Y8, and Rfp-Y9), respectively. The Rfp-Y7, Rfp-Y8, and Rfp-Y9 haplotypes have not been described previously. The Rfp-Y5 haplotype was most frequent (0.70) in line N, but existed in low frequency (approximately 0.04) in line P; the Rfp-Y9 haplotype was most frequent in line P (0.63), but was absent in line N. The Rfp-Y haplotypes-segregated in a Mendelian fashion in each line based on analysis of progeny from Rfp-Y heterozygous matings. The frequency of recombination between the Rfp-Y F and L loci was estimated to be less than 0.25%.
authors.affiliation: College of Veterinary Medicine, Mississippi State University, Mississippi, USA.
authors.forename: G T
authors.initials: GT
authors.lastname: Pharr
authors.forename: R L
authors.initials: RL
authors.lastname: Vallejo
authors.forename: L D
authors.initials: LD
authors.lastname: Bacon
mesh_terms: D000818:Animals; D002645:Chickens / Q000235:genetics*; D015342:DNA Probes; D005805:Genes, MHC Class I; D005802:Genes, MHC Class II; D006239:Haplotypes; D006579:Heterozygote; D006720:Homozygote; D012150:Polymorphism, Restriction Fragment Length; D011995:Recombination, Genetic
chemical_list: D015342:DNA Probes