Genetics might play a part in determining how religious a person is, according to a recent study by University researchers published in The Journal of Personality.

Environmental factors play a significant role in dictating how religious a person is during childhood, said Laura Koenig, the study’s lead author. But a genetic tendency toward religiousness has more of an influence in adulthood, she said.

Early in life, children’s families have a considerable effect on how religious a child is. As a person grows up and moves out of the home, genes play a more dominant role than environment does, said Koenig, a University psychology graduate student.

“As an adult, your genetic predisposition becomes more important in determining the difference in religiousness between people,” she said.

Koenig evaluated surveys of 169 pairs of identical twins, who share the same genetic makeup, and 104 pairs of fraternal twins, who share approximately 50 percent of the same genes. All the pairs of twins were men in their 30s, Koenig said.

The twins were asked questions about how often they attended religious services, prayed and observed religious holidays in childhood and adulthood.

Early in life, both fraternal and identical twins were similar in religiousness. But in adulthood, similarity between fraternal twins dropped, while identical twins maintained their religious similarities, Koenig said.

Genes cannot singularly dictate how religious a person is, but genetics definitely play a role in religiousness, she said.

“Genes don’t necessarily determine behavior,” she said.

“They make you more predisposed to certain behaviors,” Koenig said. “But you’re always acting within the context of the environment.”

Elving Anderson, a retired professor of epidemiology, said the study is interesting because it concerns the transition college students might encounter in their religious feelings.

Christopher Cook, president of the Maranatha Christian Fellowship on campus, read the study and said there were serious flaws in its conclusions in terms of causation.

“To assume a cause-and-effect relationship between genetics and religious faith is ludicrous,” said Cook, a statistics graduate student. “You can notice correlations and associations between variables, but you can’t conclude that one causes the other.”

Cook said that because a controlled environment, in which one twin would have been raised in religious surroundings and the other in an atheist environment, would have been unethical, this study is more observational than experimental.

“The fact that this stuff gets published in learned journals is laughable,” he said.