Twins study examines interaction of nature and nurture

Leila Ruiz

A UT psychology research project aims to compile and study a diverse registry of twins in hopes of better understanding the balance between a child’s genetic makeup and their environment.

The Twin Project, which started active recruitment of twins and other multiple births in 2010, asks participating children — and their parents — about the children’s personality, academic expectations, interests, peer groups and family environment. One-on-one testing is also done with each twin on their reasoning and memory abilities, as well as tendencies towards risk-taking and other behavioral indicators of maturity.

The project targets students enrolled in 32 school districts in the Houston and Austin areas, which contain over 1 million students. Approximately 54 percent of the students in the targeted districts are classified as economically disadvantaged, and 73.1 percent identify as members of racial minorities.

“We are interested in studying twins from all socioeconomic and racial backgrounds,” Elliot Tucker-Drob, psychology assistant professor and co-director of the project, said. “This contrasts with many other twin studies, which tend to be composed mostly of white participants from higher socioeconomic backgrounds.”

Psychology graduate student Daniel Briley, who has focused on the effects of parental educational expectations on children, said he was surprised to discover that children’s behavioral characteristics often play a part in altering their parents’ expectations.

“Previous research has implied that parents generate expectations and then pass on these beliefs to their children,” Briley said. “My research suggests that the formation of expectations is a two-way street … My perspective is that children are active agents in their development and the parenting that they receive.”

Studio art freshman Katherine Ray said the constant comparison between her and her twin made them more competitive as children. 

“When we were younger, we would do sports together, so people would compare us,” Ray said. “Once we got older, we developed a lot of different interests, and that was a conscious decision.”

The research looks at gene-by-environment interaction, which is how genes and environments work together to influence development. An example of this interaction is that people who are genetically predisposed to high academic achievement perform even better if they’re raised in a supportive atmosphere.

“The gene-environment interaction framework that I described earlier is one that challenges old ways of thinking about ‘nature vs. nurture,’” Tucker-Drob said. “The new question is how nature and nurture go together.”