The Lesch lab will explore how heritable changes in chromosome structure contribute to development and disease. The activity of a particular gene is controlled, in part, by whether it is loosely or tightly packaged within chromosomal DNA. As a postdoctoral fellow, I discovered that, in germ cells—which give rise to sperm or to eggs—genes that regulate embryonic development sit “poised” for action in an intermediate state of packaging. Now, combining sophisticated techniques in developmental biology, genomics, and computational analysis, my lab will search mammalian germ cells to define the packaging states of developmental genes, and use this information to characterize how these genes have evolved to regulate traits that are uniquely human, such as the specialization of brain regions involved in language and speech. In addition, because cancers often co-opt developmental genes, we will assess whether genes that adopt inappropriate packaging states in germ cells are primed to initiate tumors in later life. This work could lead to new approaches to predicting or treating cancer and developmental disorders.