Emilie Rissman
Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, USA
More than fifty years ago the discovery that manipulation of androgen exposure in neonates affected adult sexual behavior lead to a new paradigm and many subsequent studies of sexual differentiation of brain and behavior. Without a doubt exposure to steroid hormones during development shapes neural development and subsequently behaviors. This paradigm has been used to examine a variety of behaviors and sex differences in a number of parts of the brain. But in healthy fields paradigm shifts are useful and about 15 years ago another mechanism for sexual differentiation was proposed. Simply put the idea was that genes on sex chromosomes might influence sex differences in brain and behavior. Many behavioral and non-behavioral phenotypes are affected by sex chromosome complement including; autoimmune function, pain perception, social behaviors, habit formation, and neural tube development. One behavior we have studied in this regard is male sexual behavior. In typical tests of male sexual behavior when all mice are gonadectomized and treated with testosterone females are faster to mount and thrust and display more of this behavior than males. In this talk I will present data on an X-chromosome gene that we have identified as the causal factor contributing to sex differences in mounting and thrusting behavior in mice. I will also discuss the mechanism of action of this gene.
This work is supported by NIH NS055218.