title: No Distinction of Orthology/Paralogy between Human and Chimpanzee Rh Blood Group Genes.
abstract: On human (Homo sapiens) chromosome 1, there is a tandem duplication encompassing Rh blood group genes (Hosa_RHD and Hosa_RHCE). This duplication occurred in the common ancestor of humans, chimpanzees (Pan troglodytes), and gorillas, after splitting from their common ancestor with orangutans. Although several studies have been conducted on ape Rh blood group genes, the clear genome structures of the gene clusters remain unknown. Here, we determined the genome structure of the gene cluster of chimpanzee Rh genes by sequencing five BAC (Bacterial Artificial Chromosome) clones derived from chimpanzees. We characterized three complete loci (Patr_RHα, Patr_RHβ, and Patr_RHγ). In the Patr_RHβ locus, a short version of the gene, which lacked the middle part containing exons 4-8, was observed. The Patr_RHα and Patr_RHβ genes were located on the locations corresponding to Hosa_RHD and Hosa_RHCE, respectively, and Patr_RHγ was in the immediate vicinity of Patr_RHβ. Sequence comparisons revealed high sequence similarity between Patr_RHβ and Hosa_RHCE, while the chimpanzee Rh gene closest to Hosa_RHD was not Patr_RHα but rather Patr_RHγ. The results suggest that rearrangements and gene conversions frequently occurred between these genes and that the classic orthology/paralogy dichotomy no longer holds between human and chimpanzee Rh blood group genes.
authors.affiliation: Division of Population Genetics, National Institute of Genetics, Mishima, Japan Present address: Department of Biomolecular Functional Engineering, College of Engineering, Ibaraki University, Hitachi, Japan tkitano@mx.ibaraki.ac.jp.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kitano
authors.affiliation: Division of Population Genetics, National Institute of Genetics, Mishima, Japan Present address: Marine Ecosystem Research Division, Korea Institute of Ocean Science and Technology, Ansan, Korea.
authors.forename: Choong-Gon
authors.initials: CG
authors.lastname: Kim
authors.affiliation: Laboratoire d'Immunogénétique Moléculaire (LIMT, EA3034), Faculté de Médecine Purpan, Université Paul Sabatier, Toulouse III, France.
authors.forename: Antoine
authors.initials: A
authors.lastname: Blancher
authors.affiliation: Division of Population Genetics, National Institute of Genetics, Mishima, Japan.
authors.forename: Naruya
authors.initials: N
authors.lastname: Saitou
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D019143:Evolution, Molecular; D020131:Genes, Duplicate / Q000235:genetics; D006071:Gorilla gorilla / Q000097:blood / Q000235:genetics; D006801:Humans; D002679:Pan troglodytes / Q000097:blood / Q000235:genetics*; D010802:Phylogeny; D012204:Rh-Hr Blood-Group System / Q000235:genetics*; D016415:Sequence Alignment
chemical_list: D012204:Rh-Hr Blood-Group System
keywords: gene duplication; phylogeny; rearrangement