A polymorphic major histocompatibility complex class II-like locus maps outside of both the chicken B-system and Rfp-Y-system.
Chickens have two major regions encoding major histocompatibility complex (MHC) class Ialpha genes and MHC class IIss genes, the serological and functional B-system and the Rfp-Y-system. Recently, they have been shown to assort in a genetically independent way although still located on the same microchromosome. Moreover, the monomorphic MHC class IIalpha gene maps at a third locus located 5 cM from the nearest class IIss genes, located in the B-system (Kaufman et al., 1995). A pedigree family was studied in three generations in order to assign MHC class IIss restriction fragments observed in Southern blot analyses to either the B-system, the Rfp-Y-system or the B-Lalpha locus. In this study, we demonstrate by classical genetic testing of chickens within this fully pedigreed family the existence of an MHC class II-like polymorphic restriction fragment that segregates independently of the B-system, the Rfp-Y-system and of the B-Lalpha locus.
Juul-Madsen
H R
HR
Danish Institute of Agricultural Sciences, Department of Animal Health and Welfare, DK-8830 Tjele, Denmark.
Dalgaard
T S
TS
Guldbrandtsen
B
B
Salomonsen
J
J
D000483:Alleles; D000818:Animals; D002645:Chickens; D002874:Chromosome Mapping; D005802:Genes, MHC Class II; D008040:Genetic Linkage; D010375:Pedigree; D011110:Polymorphism, Genetic