Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 7/1/2003
Publication Date: 8/10/2003
Citation: Palti, Y., Phillips, R.B., Rodriguez, M.F., Hansen, J.D. 2003. Characterization and mapping of mhc haplotypes in rainbow trout (oncorhynchus mykiss). 133d Meeting of American Fisheries Society. p.251. Interpretive Summary:
Technical Abstract: Heterozygosity of major histocompatibility complex (MHC) genes in natural populations is typically very high, and is thought to be associated with a selective advantage against multiple infections. It addition, MHC haplotypes have been implicated in mate choice in Atlantic salmon. Molecular markers derived from MHC genes are widely used in population genetics studies that compare and estimate genetic diversity. The genomic architecture of the MHC in bony fish is rather complex as the class I and class II genes for rainbow trout are found on at least two different linkage groups and some of them may be duplicated. Our goal is to sequence the entire MHC class I and II regions from rainbow trout for functional genomic studies and for developing markers that can be readily used in disease resistance studies of aquaculture strains. These tools and our improved understanding of the genomic organization of the MHC in salmonid fish will be useful for population and evolutionary genetic studies. We have isolated BAC (bacterial artificial chromosome) clones harboring the MHC class Ia region including class Ia (UBA), PSMB 8-10 and ABCB3B. In addition we have isolated BAC clones containing the MHC class II genes (DAA and DAB). BACs were then labeled and used as probes for in situ hybridization on metaphase chromosomes for determining the physical location of the MHC class I and II regions. Finally, polymorphisms found within the class Ia and II regions allowed for these regions to be assigned to specific genetic linkage groups. Several BACs that contain high concentration of MHC genes are being sequenced for detailed genetic characterization, and MHC linked genetic markers (e.g. microsatellites) are being developed and characterized in rainbow trout.