Concerted evolution of the primate immunoglobulin alpha-gene through gene conversion.
We determined four nucleotide sequences of the hominoid immunoglobulin alpha (C alpha) genes (chimpanzee C alpha 2, gorilla C alpha 2, and gibbon C alpha 1 and C alpha 2 genes), which made possible the examination of gene conversions in all hominoid C alpha genes. The following three methods were used to detect gene conversions: 1) phenetic tree construction; 2) detection of a DNA segment with extremely low variability between duplicated C alpha genes; and 3) a site by site search of shared nucleotide changes between duplicated C alpha genes. Results obtained from method 1 indicated a concerted evolution of the duplicated C alpha genes in the human, chimpanzee, gorilla, and gibbon lineages, while results obtained from method 2 suggested gene conversions in the human, gorilla, and gibbon C alpha genes. With method 3 we identified clusters of shared nucleotide changes between duplicated C alpha genes in human, chimpanzee, gorilla, and gibbon lineages, and in their hypothetical ancestors. In the present study converted regions were identified over the entire C alpha gene region excluding a few sites in the coding region which have escaped from gene conversion. This indicates that gene conversion is a general phenomenon in evolution, that can be clearly observed in non-functional regions.
Kawamura
S
S
Department of Anthropology, Faculty of Science, University of Tokyo, Japan.
Saitou
N
N
Ueda
S
S
D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D004247:DNA / Q000235:genetics; D005785:Gene Conversion; D005803:Genes, Immunoglobulin; D006801:Humans; D007136:Immunoglobulins / Q000235:genetics*; D008969:Molecular Sequence Data; D005810:Multigene Family; D011323:Primates / Q000235:genetics*; D016415:Sequence Alignment
D007136:Immunoglobulins; D004247:DNA