title: Unusual HLA-B alleles in two tribes of Brazilian Indians.
abstract: The Kaingang and Guarani are culturally and linguistically distinct tribes of southern Brazil. Like all Amerindian groups they show limited HLA polymorphism, which probably reflects the small founder populations that colonized America by overland migration from Asia 11,000-40,000 years ago. We find the nucleotide sequences of HLA-B alleles from the Kaingang and Guarani to be distinct from those characterized in caucasian, oriental and other populations. By comparison, the HLA-A and C alleles are familiar. These results and those reported in the accompanying paper on the Waorani of Ecuador reveal that a marked evolution of HLA-B has occurred since humans first entered South America. New alleles have been formed through recombination between pre-existing alleles, not by point mutation, giving rise to distinctive diversification of HLA-B in different South American Indian tribes.
authors.affiliation: Department of Cell Biology, Stanford University, California 94305.
authors.forename: M P
authors.initials: MP
authors.lastname: Belich
authors.forename: J A
authors.initials: JA
authors.lastname: Madrigal
authors.forename: W H
authors.initials: WH
authors.lastname: Hildebrand
authors.forename: J
authors.initials: J
authors.lastname: Zemmour
authors.forename: R C
authors.initials: RC
authors.lastname: Williams
authors.forename: R
authors.initials: R
authors.lastname: Luz
authors.forename: M L
authors.initials: ML
authors.lastname: Petzl-Erler
authors.forename: P
authors.initials: P
authors.lastname: Parham
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D044466:Asian People / Q000235:genetics; D001483:Base Sequence; D001938:Brazil; D002461:Cell Line, Transformed; D015234:HLA-A Antigens / Q000235:genetics; D015235:HLA-B Antigens / Q000737:chemistry / Q000235:genetics*; D015236:HLA-C Antigens / Q000235:genetics; D004854:Herpesvirus 4, Human; D006801:Humans; D007199:Indians, South American / Q000235:genetics*; D008969:Molecular Sequence Data; D011110:Polymorphism, Genetic; D012689:Sequence Homology, Nucleic Acid; D044465:White People / Q000235:genetics
chemical_list: D015234:HLA-A Antigens; D015235:HLA-B Antigens; D015236:HLA-C Antigens