Dr. Hammes received his B.A. in chemistry from Cornell University in 1985, where he worked with Dr. Barbara Baird studying the IgE receptor. Dr. Hammes then entered the MD/PhD program at Duke. For his PhD, Dr. Hammes studied retroviral gene regulation with Dr. Warner Greene. He then traveled to San Francisco, where he completed an internship and residency in General Medicine, followed by a fellowship in Endocrinology. For his postdoctoral research, Dr. Hammes again chose an alternative direction, working with a cardiologist rather than an endocrinologist. He trained with Dr. Shaun Coughlin, where he studied G protein-coupled receptors.
In 1999, Dr. Hammes left UCSF to become faculty at the UT Southwestern Medical Center in Dallas, where he started an entirely new research program, choosing to study transcription-independent, or nongenomic, steroid signaling. Specifically, Dr. Hammes studies steroid-triggered maturation (meiotic progression) of oocytes, one of the few physiologically relevant steroid-triggered processes that is generally accepted to be nongenomic. Dr. Hammes has recently expanded his work to study ovarian development and function, with a focus on diseases of androgen excess such as polycystic ovarian syndrome.
Finally, in 2009 Dr. Hammes moved back to Upstate New York, where he is the Louis S. Wolk Professor of Biomedical Research and the Chief of the Division of Endocrinology at the University of Rochester Medical Center.