Related Experiment Video
Updated: Jun 5, 2026

Stability and Structure of Bat Major Histocompatibility Complex Class I with Heterologous β2-Microglobulin
Published on: March 10, 2021
Extended sequence of the turkey MHC B-locus and sequence variation in the highly polymorphic B-G loci
1Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St Paul, MN 55108, USA.
Abstract:
Genetic variation in the major histocompatibility complex (MHC) is directly correlated to differences in disease resistance. Immunity is greatly dependent on highly polymorphic genes in the MHC, such as class I, class II, and class III complement genes. Preliminary studies of wild turkey populations show extreme polymorphisms in a family of genes exclusive to the avian MHC, the class IV or B-G genes. Significance of this variation is unclear as there are few and conflicting studies of the expression of these genes. Confounding understanding of B-G variation is the lack of a complete delineation of the number of loci in the turkey genome. Direct 454 sequencing of a clone from the CHORI-260 BAC library was used to extend the turkey MHC B-locus sequence, identifying five additional complete B-locus genes including two B-G loci. Sequences of the new B-G genes were compared with those of other turkey gene (BG1-3) and sequences available for other galliformes. Phylogenetic analysis shows species-specific gene evolution supporting a birth-death model of evolution for the B-G gene family. Analysis of variation within the signal peptide sequence (exon 1) found two clusters of polymorphism among the turkey B-G genes. Resequencing of exon 1 in a diverse sample including wild, heritage, and commercial turkeys confirmed multiple alleles at each B-G gene. Future studies aim to correlate B-G variation with group and individual immunological differences.
Related Concept Videos
Single Nucleotide Polymorphisms-SNPs
Multi-species Conserved Sequences
Although the genome of each species varies greatly from each other, a few sequences are highly conserved. Such conserved DNA...
Diversity of Antigen Receptors
Before encountering any antigen, lymphocytes express these receptors. On B cells, the antigen receptor is a membrane-bound antibody molecule called BCR; on T cells, it is a T cell receptor or TCR. B and T cell receptors are composed of two...
Modern Molecular Taxonomy
Exon Recombination
Exon shuffling follows “splice frame rules.” Each exon has three reading...
General Transcription Factors
