strict warning: Only variables should be passed by reference in /usr/local/apache2/htdocs-yang/drupal6/sites/all/modules/date/date_api.module on line 866.

Nucleotide Polymorphism at the Xanthine Dehydrogenase Locus in Drosophila pseudoobscura

Authors

MA Riley, Susanne R. Kaplan, and Michel Veuille

Abstract

Sequential polyacrylamide electrophoresis has revealed 20 allozymes of xanthine dehydrogenase (XDH) in Drosophila pseudoobscura. DNA sequence determination of seven isolates of the Xdh locus that represent six allozyme classes are presented here. Of the 5,456 sites examined, 180 are polymorphic, with 27 polymorphisms occurring at nonsynonymous, or replacement, sites. An average of nine amino acids differ between XDH allozyme classes, with 85% of the polymorphic amino acids singly represented. The level and pattern of variation observed at Xdh argue that the effective population size of the species is quite large-i.e., on the order of 2 X 106- and that the populations sampled are quite ancient. In addition, as judged by two statistical tests, the levels of nucleotide polymorphism observed at Xdh are compatible with predictions from the neutral theory of molecular evolution.

Theme by Danetsoft and Danang Probo Sayekti inspired by Maksimer