Learning About Your Genetic Risks Can Impact You More Than the Genes

New research demonstrates the power of a person’s mindset. According to some of the measures used, someone just thinking they had a certain gene had a more powerful physical impact than actually having that gene. The research was published last month and comprised two studies.

For the first study, people were randomly assigned to learn their genes put them at high risk for traits associated with obesity or that they had genes that were “protective” against those same traits. Researchers conducted actual genetic testing, but some participants were assigned to receive information that didn’t reflect their actual results.

The first experiment centered on CREB1, a gene linked to having poorer aerobic capacity and fewer cardiovascular improvements when exercising. The study began with participants running on a treadmill to get baseline measures. They then returned a week later to complete another test. This time, they were told that they had the high-risk form of the gene or the protective form of the gene.

Regardless of the genes people actually had, they were told they were at high risk during the second treadmill task. These participants stopped running significantly earlier than they had the first time. They also demonstrated a lower maximum capacity for CO₂:O₂ gas exchange.

While the people who were told they had the protective gene, saw no physiological changes compared to the first test, they were able to run significantly longer before stopping than in the test a week before.

To test if the results were unique to the CREB-1 gene or if they would extend to others, a second study was put together to focus on the FTO gene. The high-risk form of FTO is associated with people feeling full more slowly than others and show lower levels of a gut peptide that signals satiety to the brain.

For this study, people ate 480-calories after fasting overnight and reported how full they felt at various points before and after eating while the peptide was measured.

Participants returned to do the test again, but this time, as with the previous study, they were told before eating that they had the high-risk or the protective form of the gene. Participants who thought they had the protective gene had 2.5 times the levels of the gut peptide and reported feeling more full. Participants told they were at high risk didn’t change significantly on either measure.

In the interest of minimizing the time participants spent believing potentially false information, they ensured that each was fully briefed before leaving the site and given their actual genetic results if they wanted them.



Image: “Touche pas à mon ADN DDC_4313.JPG” by thierry ehrmann is licensed under CC BY 2.0