Mhc-E polymorphism in Pongidae primates: the same allele is found in two different species

• Published in: Tissue antigens 1997-12, Vol.50 (6), p.695-698
• Main Authors: Suárez, B., Morales, P., Castro, M.J., Fernández-Soria, V., Recio, M.J., Pérez-Bias, M., Alvarez, M., Díaz-Campos, N., Arnaiz-Villena, A.
• Format: Article
• Language: English
• Subjects: Alleles; Animals; Base Sequence; Cell Line, Transformed; chimpanzee; DNA, Complementary; gorilla; Gorilla gorilla - genetics; Gorilla gorilla - immunology; Histocompatibility Antigens Class I - genetics; HLA Antigens - genetics; HLA-E Antigens; Hominidae - genetics; Hominidae - immunology; Humans; Major Histocompatibility Complex; Mhc-E; Molecular Sequence Data; orangutan; Pan paniscus - genetics; Pan paniscus - immunology; Pan troglodytes - genetics; Pan troglodytes - immunology; Phylogeny; Polymorphism, Genetic; Pongidae; Pongo pygmaeus - genetics; Pongo pygmaeus - immunology; Sequence Homology, Nucleic Acid; Species Specificity
• ISSN: 0001-2815; 1399-0039
• DOI: 10.1111/j.1399-0039.1997.tb02938.x

Mhc‐E intron 1, exon 2, intron 2, and exon 3 from pygmy chimpanzee (Pan paniscus), chimpanzee (Pan troglodytes), gorilla (Gorilla gorilla) and orangutan (Pongo pygmaeus) have been sequenced; six new Mhc‐E alleles have been obtained but sequence changes are only placed either in introns or in synonymous exonic bases. One pygmy chimpanzee Mhc‐E DNA sequence is identical to another sequence from chimpanzee; the fact that no variation is found also at the intronic level suggests that these two species of chimpanzee may have recently separated and/or that both of them might only represent subspecies. Mhc‐E phylogenetic trees separate two evolutionary groups: Pongidae, including humans, and Cercopithecinae; this is also found by studying another non‐classical class I gene, Mhc‐G. The Mhc‐E alleles' invariance at the protein level supports that strong selective forces are operating at the Mhc‐E locus, as has also been found in both Cercopithecinae and humans. These allelic and evolutionary data suggest an altogether different functionality for HLA‐E (and also HLA‐G) compared with classical class I proteins: i.e., sending negative (tolerogenic) signals to NK and T cells.