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Millions of people around the world are spitting into vials in hopes of learning more about their genes. But they’re not just looking for information about their ancestors.
Increasingly, people are interested in how their genes may be affecting their health, nutrition, physical potential and risk of injury.
The global market for these direct-to-consumer genetic tests is expected to increase in the coming years, soaring from $1.9 billion in 2023 to $8.8 billion in 2030, according to a market analysis report from Grand View Research. North Americans are in the lead with 60.5% of the market share, although Europe is predicted to become the fastest growing market over the next six years, the analysis shows.
In 2013, about 20 companies offered direct-to-consumer genetic testing aimed at sports performance and injury risk — a number that increased to about 70 in 2019, according to a study review. Additionally, a 2020 study published in the Indian Journal of Orthopedics reported that Uzbekistan and China are using genetic testing in their Olympic talent identification programs, while Australia’s National Rugby League players are using DNA testing to adapt your workouts for running or explosive powerlifting.
Despite all this buzz, many researchers said there is a lot of enthusiasm and little solid science behind these tests. One such skeptic is Dr. Timothy Caulfield, a professor at the law school and school of public health at the University of Alberta in Edmonton.
“I have been following this area since the late 1990s and progress has not been substantial,” Caulfield said.
There was a lot of excitement about genetic testing when scientists discovered the BRCA1 and BRCA2 genes in 1994 and 1995, respectively. Women with mutations in any of these genes have been found to have a 60% to 80% lifetime risk of breast cancer. Furthermore, a BRCA1 mutation carried a 40% to 50% lifetime risk of ovarian cancer, while a BRCA2 mutation carried a 10% to 20% lifetime risk.
“There was hope that we would find many genes like these that would be highly predictive and where we could take action to make a difference in our health,” Caulfield said. “But it really wasn’t like that.”
Instead, he said, scientists have discovered that how our genes work is a complex topic, especially when it comes to fitness and sports. Caulfield had a genetic test, for example, which showed he was unlikely to excel in running. Still, he was talented in the sport, competing throughout his childhood and college.
“There is no doubt that genes are important, but the question is how much?” Caulfield said. “Even when you look at Olympic-level long jumpers, who need highly explosive movements, not all of them have the running gene. If it really mattered, everyone would have to have it.”
In fact, scientists say there are many additional factors when it comes to sporting talent and success, such as diet, sleep, training, motivation, socioeconomic background and even experiences in the womb. Likewise, there are countless variables when it comes to injury risk.
Many factors are important when it comes to a person’s talent in sports, such as diet, sleep, training, and motivation.
Another concern among researchers is the scientific validity of these tests. While the accuracy in terms of actual genetic tests is probably good, the science behind how companies are interpreting the results could be problematic, said Dr. Dylan MacKay, assistant professor of nutrition and chronic disease at the University of Manitoba in Winnipeg, Canada. .
“Often these tests are based on associations rather than randomized, controlled trials looking for a causal effect,” MacKay said. “For example, watermelon consumption is associated with drowning – because more people swim in the same season they eat watermelons. But that’s just an association.”
The advice companies give based on their test results is also often vague or cookie-cutter. Caulfield’s results indicated that he was at risk of developing certain cardiovascular problems and cancer.
“What was my personalized advice for staying healthy? Eat well, exercise regularly, don’t smoke, drink in moderation,” Caulfield said.
Despite these questions, many remain intrigued by DNA aptitude tests. One of those people is Devin Maier, co-owner of Balance Gym in Washington, DC. Balance Gym recently partnered with FitnessGenes, a UK-based company that sells genetic testing, to help its customers get better results from their workouts.
While the tests don’t provide precise instructions for getting in shape, Maier said he believes they can be helpful. One of her clients was trying to gain muscle by lifting heavier weights, but with fewer repetitions. Test results showed that his muscle type would do better with higher volume training, so Maier had him switch to lifting lighter weights with more repetitions. Within a month or two, the client was seeing the desired muscle gains.
These tests can also help you discern your strengths and weaknesses, Maier said, so you can address them.
“You may not have the genes to be a good endurance athlete,” he said, “but if you want to run a marathon, we can help you train better so you can do it.”
Maier said he also thinks there is a lot of potential in this area.
“Our DNA is not changing, but science and information are, and will continue to change,” Maier said.
Time and other scientific advances may clarify whether DNA aptitude tests are, or can be, useful. But MacKay remains doubtful.
“I’ve been in this field a long time, and although genetic testing is getting better and better, there are no new discoveries that are groundbreaking,” he said.
Caulfield said he hopes parents don’t use these tests to force their children into — or away from — a specific sport or activity.
“Genes don’t determine whether you will enjoy a sport or be good at it,” he said. “You should do what you love and not let these genetic tests make everything more complicated than necessary.”
Melanie Radzicki McManus is a freelance writer specializing in hiking, travel and fitness.