The brain chemical dopamine may negatively impact grades, Florida State University researchers suggest.
Kevin Beaver and colleagues linked a variant in a gene known as DAT1 — with marginally negative effects on English grades and no apparent effect on math, history or science. However, a variant in the DRD2 gene correlated with a markedly negative effect on grades in all four subjects. Single DRD4 variant students had significantly lower grades in English and math, but only marginally lower grades in history and science. As certain dopaminergic gene variants increased, grade point average decreased.
“For example, the GPA of a student with specific variants of three dopaminergic genes might be around 2.8, versus a GPA of around 3.3 without the variants,” lead author Beaver said in a statement. “That could mean the difference between being accepted into a college versus being rejected.”
Beaver suggests genetic liability for low GPA could be moderated by environmental conditions such as school structural characteristics, teacher performance or behavior of other students.
The study, published in Intelligence, was based on DNA and lifestyle data from a representative group of 2,500 U.S. middle- and high-school students tracked from 1994 to 2008 as part of the National Longitudinal Study of Adolescent Health.