Bryant McAllister

Differences between the sexes exist universally among animals and plants.  How do these differences arise from the common gene pool shared by females and males, and what selective mechanisms shape these differences?  Individual genes control the primary switch in sexual development, and these often reside on a specific pair of sex chromosomes.  Due to the fact that the sex chromosomes control sex, they are not shared equally between females and males.  Our research investigates how this inequality influences the content and function of genes on the sex chromosomes.  Using a natural chromosomal rearrangement in the fly Drosophila americana, which recently generated a new pair of sex chromosomes, these studies indicate that section pressures unique to females and males shape gene content and variation on the sex chromosomes. Selection to optimize female function appears to have an overwhelming influence on the sex chromosomes.

Biography Bryant McAllister

Bryant McAllister obtained a BS in zoology and MS in genetics from Texas A&M University.  After earning a PhD in biology from the University of Rochester, he was awarded an Alfred P. Sloan/National Science Foundation Postdoctoral Fellowship in Molecular Evolution.  He is currently Associate Professor of Biology in the UI College of Liberal Arts and Sciences, a faculty member in the interdisciplinary PhD program in genetics, a member of the Roy J. Carver Center for Comparative Genomics, and a 2008 Dean’s Scholar.  His primary teaching responsibility at The University of Iowa is an undergraduate course in evolution.  Grants from the National Science Foundation and the Roy J. Carver Charitable Trust have supported McAllister’s research, which studies general principles governing the organization of genes within chromosomes.  Most of his research uses flies in the genus Drosophila, and especially Drosophila americana, as a system for studying genome evolution.  These are inconspicuous flies that feed on a variety of decaying plant matter.  McAllister was on the initial planning committee and contributed to the recently completed 12 Drosophila Genomes project, which represents the most comprehensive study of evolutionary change across the genome.  Ongoing projects in his laboratory address both the processes affecting the establishment of new chromosomal arrangements and the consequences of large-scale changes in genome organization.  He was been at the UI since 2002.