title: Evolutionary expansion of Mhc class I loci in the mole-rat, Spalax ehrenbergi.
abstract: A cosmid genomic library was prepared from a single individual of the rodent Spalax ehrenbergi, the mole rat, captured in Israel. The library was screened with a mouse probe hybridizing with all mouse class I major-histocompatibility-complex (Mhc) genes; the cross-hybridizing clones were isolated; and their restriction maps were prepared using five enzymes. A total of 93 class I-bearing clones could be identified in the library. Forty-five of these clones showed partial overlaps and could be arranged into 14 clusters. Eleven of these clusters could be shown to contain two class I genes each; the remaining clusters, as well as most of the non-overlapping clones, each contained one class I gene. After the elimination of clones with possible cloning artifacts and of clones that may carry allelic forms of a given gene in the heterozygous animal, the total number of class I loci identified in Spalax is approximately 65. The high number of loci probably arose from the duplication of either the entire class I set or the different class I families. The high number of gene copies might represent a means of selecting different functional genes from the family in different mammalian orders. Three of the approximately 65 Spalax class I genes cross-hybridize with a probe specific for the mouse K, D, and L genes; two of these genes are in the same cluster. These three elements might possibly be the functional class I genes of the mole rat.
authors.affiliation: Max-Planck-Institut für Biologie, Abteilung Immungenetik, Tübingen, Federal Republic of Germany.
authors.forename: V
authors.initials: V
authors.lastname: Vincek
authors.forename: D
authors.initials: D
authors.lastname: Nizetić
authors.forename: M
authors.initials: M
authors.lastname: Golubić
authors.forename: F
authors.initials: F
authors.lastname: Figueroa
authors.forename: E
authors.initials: E
authors.lastname: Nevo
authors.forename: J
authors.initials: J
authors.lastname: Klein
mesh_terms: D000818:Animals; D005075:Biological Evolution; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D008285:Major Histocompatibility Complex; D012377:Rodentia / Q000235:genetics*