The primary objectives of this research are to assess restriction-site and DNA-sequence variation within the region common to pericentric inversions of chromosome 6 in the common deer mouse (Peromyscus maniculatus), and to determine whether linkage disequilibrium exists between specific DNA haplotypes and each of the three morphs of this chromosome. These data will be used to evaluate two alternative hypotheses for the origin (monophyletic or convergent) and maintenance (selection or recurrent mutation) of the widespread pericentric-inversion polymorhisms in P. maniculatus and the related deer mouse species P. sitkensis and P. oreas. The sample will include deer mice collected from natural populations throughout North America. The pericentric-inversion system of P. maniculatus represents an ideal mammalian model to test the general applicability of the genetic hypotheses and evolutionary principles derived from the paracentric-inversion system of the fruit fly Drosphila pseudoobscura.
