What do children born during severe snowstorms in Canada, sufferers of post-traumatic stress disorder, and malnourished male mice have in common? All of them experience large changes in the genes that control the immune response, including inflammation. And the effects don’t just stay with them—in the case of the mice, they’re passed on to offspring.
Trauma in the genetic past, in fact, may go a long way toward explaining one of the persistent inequalities of American public health: The age-adjusted death rate for African-Americans is 18.3 percent higher than whites. African Americans are 30.1 percent more likely to die of cardiovascular disease, and 99.4 percent more likely to die of diabetes than whites.. Both of these conditions are aggravated and made more lethal by inflammation.
Acknowledging a health burden still being borne by descendants of African American slaves would contribute to the national dialogue on a society that remains persistently unequal.
There is good reason to believe that the descendants of former slaves are still carrying the mark of the lash deep within their genome. If experiencing a severe snowstorm can cause epigenetic changes in genes that control inflammation in children—as Project Ice Storm, a study from McGill University of children born during the 1998 Quebec snowstorm, recently showed—children born to mothers experiencing the unimaginable stress of slavery likely had similar changes. Such changes are inherited over a single generation each time, as has been shown to happen in mice in work recently published in the journal Cell Metabolism. One can see how the echoes of systematic brutality may have effects on contemporary generations of African Americans, significantly affecting their health.
The high prevalence of chronic diseases of inflammation in the African-American population could undoubtedly be attributed to a constellation of causes, including diet and exercise habits, as well as less access to healthy foods and health care. African Americans have higher rates of both adult and childhood obesity, and are more likely to live in food deserts, where local supermarkets sell far more processed and unhealthy foods instead of fresh fruits and vegetables. But let’s not overlook the deeply traumatic experiences of slavery, and the conditions under which African Americans lived during Jim Crow; epigenetic changes are almost certainly borne by today’s generation of African Americans.
This matters to everybody, and not merely for altruistic reasons. With such chronic sickness out of control, the cost of health care gets more expensive for everyone.
The good news is that epigenetic changes have been shown to be reversible with drugs currently being used in the clinic against cancers such as acute myeloid leukemia and chronic myeloid leukemia, and more research into the causes of these clear health disparities, including potential epigenetic changes, would go a long way to treating such diseases.
Acknowledging a health burden still being borne by descendants of African American slaves would contribute to the national dialogue on a society that remains persistently unequal. What we are now beginning to understand with frightening clarity is just how deep that inequality remains under the skin.