title: Molecular evidence to suggest the origin of a colonization: Drosophila subobscura in America.
abstract: The recent colonization of America by Drosophila subobscura represents a great opportunity for evolutionary biology studies. Knowledge of the populations from which the colonization started would provide an understanding of how genetic composition changed during adaptation to the new environment. Thus, a 793 nucleotide fragment of the Odh (Octanol dehydrogenase) gene was sequenced in 66 chromosomal lines from Barcelona (western Mediterranean) and in 66 from Mt. Parnes (Greece, eastern Mediterranean). No sequence of Odh fragment in Barcelona or Mt. Parnes was identical to any of those previously detected in America. However, an Odh sequence from Barcelona differed in only one nucleotide from another found in American populations. In both cases, the chromosomal lines presented the same inversion: O(7), and the Odh gene was located within this inversion. This evidence suggests a possible western Mediterranean origin for the colonization. Finally, the molecular and inversion data indicate that the colonization was not characterized by multiple reintroductions.
authors.affiliation: Departament de Genètica, Facultat de Biologia, Universitat de Barcelona, Av. Diagonal 643, Barcelona, Spain.
authors.forename: Pedro A
authors.initials: PA
authors.lastname: Araúz
authors.forename: Francesc
authors.initials: F
authors.lastname: Peris-Bondia
authors.forename: Amparo
authors.initials: A
authors.lastname: Latorre
authors.forename: Luís
authors.initials: L
authors.lastname: Serra
authors.forename: Francesc
authors.initials: F
authors.lastname: Mestres
mesh_terms: D000569:Americas; D019943:Amino Acid Substitution; D000818:Animals; D005075:Biological Evolution; D007446:Chromosome Inversion; D004330:Drosophila / Q000145:classification / Q000235:genetics*; D005260:Female; D051456:Gene Flow; D017344:Genes, Insect; D006115:Greece; D006239:Haplotypes; D008297:Male; D010802:Phylogeny; D011110:Polymorphism, Genetic; D011157:Population Dynamics; D013030:Spain