Sequence Analysis of Goat Major Histocompatibility Complex Class I Genes

The polymorphism of major histocompatibility complex (MHC) class I genes has been often involved in the resistance/susceptibility to a variety of infectious and parasitic diseases. In this work, the complete sequence of the coding region of a major histocompatibility complex (MHC) class I gene in goats (Cahi-N*01701, GenBank accession no. EF569216) is reported. The length of the corresponding open reading frame was 1,077 bp encoding a mature protein of 337 amino acids. Sequencing of additional clones allowed us to identify a second locus (Cahi-NC4*50301, GenBank accession no. EF569217) that, after performing a Bayesian phylogenetic analysis, happened to cluster with a bovine non-classical MHC class I gene. Nonclassical MHC class I molecules display low levels of polymorphism and fulfill an important immunoregulatory role in the placenta to inhibit maternal rejection. This initial description of the gene content of the goat MHC class I region will contribute to the characterization, in this ruminant species, of one of the most important genetic factors in the elicitation of innate and adaptive immune responses against pathogens.