Great-grandma Could Be the ‘Ghost in Your Genes’

PULLMAN, Wash. – Your great-grandmother being exposed to an environmental toxin during pregnancy could explain why you suffer from a disease today.

Michael Skinner, Washington State University molecular biologist, said this groundbreaking discovery could lead to a paradigm shift in our understanding of disease that could affect medicine, toxicology—even evolution.

Skinner will discuss his research in “Epigenetics, Heredity, and the Environment: The Ghost in Your Genes” March 22 at the Rainier Club, 820 4^th Ave., Cutter Room, Second Floor, in Seattle. Tickets are $30 per person and include lunch from noon to 1:30 p.m., with registration to begin at 11:30 a.m. To reserve a spot, visit https://www.wsu.edu/theinnovators/. Registration will continue until capacity is reached.

WSU researchers found that environmental toxins can alter the activity of an animal’s genes in a way that is transmitted through at least four generations after the exposure. Their discovery suggests that toxins may play a role in heritable diseases that were previously thought to be caused solely by genetic mutations. It also hints at a role for environmental impacts during evolution.

“It’s a new way to think about disease,” said Skinner, director of the WSU Center for Reproductive Biology. “We believe this phenomenon will be widespread and be a major factor in understanding how disease develops.”

Skinner’s research found that when pregnant rats were exposed to environmental toxins to gauge the effect on testis development, the immediate male offspring as well as the next two generations of male pups had lowered sperm counts. As the animals aged a host of diseases from cancer to immune dysfunction developed for all generations examined.

These epigenetic changes, or changes that occur due to chemical modification of the DNA, altered the function of the genes similar to flipping a light switch. The implications for human health include the possibility that events in a person’s lifetime—such as exposure to toxicants, stress, or disease—could affect that person’s descendants several generations later.

Skinner’s research grabbed worldwide attention when his findings were published in the journal Science last June. The January 2006 issue of Discover included his work on its list of the “100 top science stories of 2005.”