The MHC class I genes of the rhesus monkey. Different evolutionary histories of MHC class I and II genes in primates.
Homologues of the human HLA-A and -B MHC class I loci have been found in great apes and Old World primates suggesting that these two loci have existed for at least 30 million years. The C locus, however, shows some sequence similarity to the B locus and has been found only in gorillas, chimpanzees, and humans. To determine the age of the MHC class I C locus and to examine the evolution of the A and B loci we have cloned, sequenced, and in vitro translated 16 MHC class I cDNAs from two unrelated rhesus monkeys (Macaca mulatta) using both cDNA library screening and PCR amplification. Analyses of these sequences suggest that the C locus is not present in the rhesus monkey, indicating that this locus may be of recent origin in gorillas, chimpanzees, and humans. The rhesus monkey's complement of MHC class I genes includes the products of at least one expressed A locus and at least two expressed B loci, indicating that a duplication of the B locus has taken place in the lineage leading to these Old World primates. Comparison of rhesus monkey MHC class I cDNAs to their primate counterparts reveals fundamental differences between MHC class I and class II evolution in primates. Although MHC class II allelic lineages are shared between humans and Old World primates, no such trans-species sharing of allelic lineages is seen at the MHC class I loci.
Boyson
J E
JE
University of Wisconsin, Madison, WI 53715, USA.
Shufflebotham
C
C
Cadavid
L F
LF
Urvater
J A
JA
Knapp
L A
LA
Hughes
A L
AL
Watkins
D I
DI
D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D017931:DNA Primers / Q000737:chemistry; D018076:DNA, Complementary / Q000235:genetics; D005805:Genes, MHC Class I; D005802:Genes, MHC Class II; D008253:Macaca mulatta / Q000235:genetics*; D008969:Molecular Sequence Data; D010802:Phylogeny; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
D017931:DNA Primers; D018076:DNA, Complementary