common genetic variant that changes how your brain is wired during adolescence could help explain why anxiety disorders most often strike in the teen years, a new study finds.
Why it matters:
Medications currently used to treat anxiety disorders are often informed by studies of the adult brain. “Kids are not mini-adults,” said lead investigator Dylan Gee of the Weill Cornell Medical College at Cornell University. So it’s important to use developmental neuroscience to create better therapies for teens.
The nitty gritty:
Previous studies have shown that adults with a certain version of the FAAH gene, known as FAAH C385A, reported less anxiety and showed slightly different brain connections — their prefrontal cortex was more tightly wired to deeper parts of the brain where emotional memories are stored.
But scientists wanted to see how that changed over time. They examined data from 1,050 healthy participants, ages 3-21, including their genotype, psychological assessments, and brain scans. They found that those with the protective C385A allele showed higher frontolimbic connectivity and lower self-reported anxiety — but only after 12 years of age. In children younger than 12, the gene didn’t have noticeable anxiety effects. That indicates that the changes in gene activity over time may lead to the development of anxiety disorders.
But keep in mind:
While this certain version of the FAAH gene is associated with decreased anxiety, anxiety is a complex disorder that develops from the interplay between many gene variations and experiences. At this point genetic testing would not be helpful, said Jehannine Austin, associate professor at the University of British Columbia. This variant is just “one of a whole large number of different genetic variants that can increase or decrease vulnerability,” she explained.
The bottom line:
Understanding the variety of genes that influence brain wiring and biochemistry at different ages is key to developing tailored treatments for psychiatric patients in the future. This study provides a small but promising step towards that goal, said Dr. Claes Wahlestedt of the University of Miami Miller School of Medicine.