Genetics

Epigenetics and Intergenerational Health

By Wren Greaney, History major, Biological Sciences & Community Development minor, ’17

Author’s Note: “I became interested in the impact of epigenetics after reading an article about the effects of environmental pollution on generations beyond the population subjected to the pollution. So much focus in human biology is placed on genetics; it is fascinating that a closely related and significant topic exists that is unique from genetics itself. As epigenetic research progresses, I think it will find a large role in advancing healthcare as well as our understandings about humans’ biological identities.”

At the forefront of genetic research is an area that extends beyond the genome’s contents. The mounting research in the growing field of epigenetics indicates that a key to limiting health vulnerabilities in future generations is an investigation into greater interventions for the current population. The field also presents society with a new perspective to grapple with regarding the biological factors that respond to and shape our experiences.

Epigenetic factors function by modifying DNA expression through the attachment of methyl groups and histones to DNA in a cell’s nucleus. These chemical groups and proteins work to either silence or activate genes, altering the expression of genetic material.[1] Epigenetic factors can change in response to environmental factors such as chemical exposure or nutrition.[2]

Epigenetic inheritance is the process by which offspring can sometimes inherit the altered state of their parents’ genes. Thus, the effects of epigenetic alterations could be carried from the parent who experienced the environmental stimulus to offspring who have not. Since epigenetic alterations can lead to health issues, this inheritance process has implications for the occurrence of various health problems through generations. Further research is needed, however, to determine the extent to which epigenetic inheritance impacts offspring’s traits.

A recent study by the University of California, San Francisco (UCSF) found that epigenetic markers appear to be shared within ethnic groups.[5] The study’s significance lies in the fact that, according to co-author Esteban Burchard, MD, MPH of UCSF, “this is the first time anyone has attempted to quantify the molecular signature of the non-genetic components of race and ethnicity.” The researchers indicated that further studies in the future could show that these shared epigenetics may be due to shared environmental experiences.

As findings emerge regarding ethnic factors and inheritance of various traits, some note that this information may fall victim to a eugenic concept that has been prominent at various times, especially during the early 20th century.[6] Eugenics involves the racist notion that certain populations, particularly non-whites, should not be allowed to produce offspring due to a perceived biological inferiority. The sociologist Maurizio Meloni remarked that “epigenetics has the potential to advance social justice” by focusing on limiting the negative environmental factors that create epigenetic harm, and that it “is important to keep talking about these issues, before minority groups such as racists try to hijack epigenetics to further their cause.”

The real impacts of epigenetic alterations may be demonstrated through ongoing instances. A recent New York Times article noted that scientists have questioned whether the “public humiliation, political exile and starvation” that occurred in China under Mao Zedong may have impacted younger generations’ psyches through epigenetic inheritance. [3] Likewise, children of Holocaust survivors are more likely to experience stress-related illnesses, and their stress genes have shown epigenetic markers that are identical to markers on the genes of their parents who endured the Holocaust. [4]

Ultimately, the new information from UCSF, and the growing field in general, indicates potential for a greater understanding of epigenetic factors that impact health within various populations. This research may prove useful to address widespread health challenges, and a constructive dialogue may circumvent a “hijacking” by eugenicists.

 

Sources

[1] Uppsala Universitet. “A new principle for epigenetic changes.” ScienceDaily. ScienceDaily, 20 January 2017.

 

[2] University of Cambridge Research Community. “Scientists discover how epigenetic information could be inherited.” 25 January 2013.       

 

[3] Helen Gao. “A Scar on the Chinese Soul.” New York Times, 18 January 2017.

 

[4] Helen Thomson. “Study of Holocaust survivors finds trauma passed on to children’s genes.” The Guardian, 21 August 2015.

 

[5] University of California – San Francisco. “Cultural differences may leave their mark on DNA.” ScienceDaily. ScienceDaily, 10 January 2017.

 

[6] Maurizio Meloni. “If we’re not careful, epigenetics may bring back eugenic thinking.” The Conversation, 15 March 2016.   
Edited by Rachel Hull, Nicole Strossman, and Madison Dougherty