Student Researcher Examines Genetics Variation and Personality

Senior Cassandra White received the Undergraduate Research Award to study how genetic variation impacts primate personalities.

January 30, 2020

Cassandra White

Cassandra White, a senior majoring in biology and public health, became interested in research after taking a class on human evolutionary genetics. (Harrison Jones/ GW Today)

By Kristen Mitchell

Cassandra White, a senior majoring in biology and public health, is researching what kind of impact genetic and environmental factors have on primates’ personality—a key question in the debate on how behavior is influenced by nature and nurture.

Ms. White is looking at the DNA of chimpanzees and comparing that with validated personality data available to the Center for the Advanced Study of Human Paleobiology. In her preliminary work, she honed in on the DRD2 gene, the methylation of which was found to be associated with the personality dimensions of openness and extraversion.

Methylation is the addition of a -CH3 tag to DNA, which can affect how genes are expressed without changing the coding sequences in the DNA. Methylation can be influenced based on environmental factors.

Ms. White’s research examines how methylation and coding variation in DRD2 influences the gene’s expression as receptors, membrane-bound molecules that detect signals from outside of the cell and activate changes inside the cell based on these signals. Ms. White is specifically examining the DRD2 gene that codes for a key dopamine receptor, which regulates the creation and release of dopamine.

She hopes this project will contribute to the greater understanding of the genome of the chimp, the closest relatives to humans.  

“I think this research specifically can contribute to the idea that the nature versus nurture paradigm is just a false dichotomy,” she said. “It’s not one single thing that affects your whole outcome.”

Ms. White received an Undergraduate Research Award to explore this work, which she does under Brenda Bradley, associate professor of anthropology. Ms. White came to GW as a biology major and was inspired to pursue research after taking Dr. Bradley’s Human Evolutionary Genetics course as a first-year student.

One day after class, Ms. White went to talk to Dr. Bradley about her work and was offered a spot in her lab as a volunteer. She has been working in the lab ever since and has gained more freedom over time to pursue independent projects—an experience she finds equally terrifying and exciting.

“Research in general always keeps you on your toes, and I like that,” she said. “It’s never boring because you can have several different outcomes at any one time.”

Dr. Bradley said Ms. White’s proactive desire to learn as much as possible in the lab helped make her a successful researcher.

“She was willing to work on a variety of different things and was very adaptable,” Dr. Bradley said. “Then she found a way, still, to go back to her original interest in epigenetics—taking the toolset she had already developed and applying it to her own project.”

As a volunteer, Ms. White assisted a graduate student on a project about lemur genetics and was able to generate enough data to complete her own research analysis. She presented this work at a regional conference.

Ms. White plans to present her work at the annual GW Research Showcase on April 7. She was also invited to speak about her work at the American Association of Physical Anthropologists (AAPA) conference in Los Angeles this spring.

Ms. White said she encourages all students to pursue research opportunities during their time at GW. While finding opportunities can be intimidating, she said students should pursue subjects that excite them and go from there.

“When I found my class with Dr. Bradley it was not a required class, I just took it because it sounded interesting,” she said. “So go out on a limb like that, and when you find something you like, don’t be afraid to ask the professor about it.

“You might feel like you don’t know enough about the topic, but you’ll learn as you get more experience.”

Ms. White plans to graduate in May and hopes to continue working in a lab pursuing research. She wants to eventually pursue a Ph.D. in genetics or epigenetics, a field that specifically explores gene expression.

To learn more about available research opportunities contact the GW Center for Undergraduate Fellowships and Research.