Julie A. Douglas, Ph.D.

Most ordinary traits and common diseases in humans are heritable. In fact, the genetic bases of many traits and diseases from height to breast cancer to longevity have been recognized for nearly a hundred years. However, it is only recently that we have had the tools and resources required to search for their genetic underpinnings.

The goal of the Douglas lab is to apply, adapt, and develop a variety of statistical and computational tools and contemporary resources to identify the genetic contributions to medically important traits and common diseases in human populations. For example, a major, current aim in the lab is to discover the genetic factors that influence breast density, the third strongest risk factor for breast cancer, after age and mutations in the BRCA1 and BRCA2 genes.

Because most medically important traits like breast density are complex, being influenced by an inter-play of both genetic and non-genetics factors, study design is critically important. To this end and in an effort understand the genetic basis of breast density, we recently recruited and characterized a sample of approximately 1,500 Amish women with respect to multiple breast cancer risk factors, including breast density. One of the advantages of studying the Amish is that they have unique cultural and reproductive behaviors that reduce the effect of non-genetic factors - such as delayed childbearing and the use of contraceptives and female hormones - that affect breast density.