Part neurologist, part philosopher, 73-year-old Stefánsson has become increasingly convinced that the complex cocktail of DNA we inherit from our parents, including about 70 spontaneous genetic mutations which we acquire by chance, subconsciously dictates our behavior to a far greater extent than we know.
We may not realize it, but it appears that many routine aspects of our daily lives may be partially driven by our genome. Subtle genetic tweaks to your taste receptors help determine whether you prefer drinking coffee or tea. That’s it that coffee lovers are less sensitive to the bitterness of caffeine, while tea lovers are less sensitive to other types of bitter chemicals.
Genetics also play a role when it comes to our likes or dislikes for all kinds of different activities. On a simplistic level, it manages both how happy you are exercise, and if you prefer more solitary forms of physical activity such as running, or competing with others as part of a team sport. But our DNA may also point us towards more specific leisure pursuits.
Fifteen years ago, a survey of 2,000 British adults first suggested that there might be such a thing as a hobby gene. A simple look at one’s family tree and the favorite pastimes of their ancestors suggests a strong inclination towards certain types of activities. Survey participants are often surprised to discover that they actually come from a long line of novice gardeners, stamp collectors, or cake makers.
In the following decade, many people around the world referred to the study after realizing that a parent’s or grandparent’s favorite pastime suddenly had an inexplicable appeal in old age. In a Medium blogMichael Woronko, an insurance worker from Ottawa, Canada wrote, “I never showed any interest in gardening, even when I was young my mother dragged me to her community garden. I didn’t care for hybrid tomatoes. , about the sprouted peppers, and so on, but when the opportunity arose (as an adult), something inside of me popped up and I ran with it”.
Large genomic sequencing studies are now beginning to explain why. Stefánsson describes how deCODE scientists found a specific gene variant that determines whether crossword puzzles appeal to you. “We know that if you have one, you want to solve crossword puzzles, but it doesn’t matter whether you’re good at them or not,” he laughs.
The same is true when it comes to the complex matter of how our genes dictate the life paths we follow.
From Boston to Shenzhenvarious tech start-ups have spent years searching for the so-called talent genes, genetic variants that can confer innate strength or unique language abilities, allowing a person to be directed to the areas where they have the most to offer.
But doing so is not as simple as it may seem. Geneticists at the Max Planck Institute in Leipzig, Germany, have recently tried to draw connections between a gene called ROBO1 that controls the development of gray matter in a part of the brain involved in number representation, and a child’s math abilities. But nowadays it seems that of all talents, whether it’s number crunching, musical ability, or athletic prowess, genetics is only a relatively small part of the equation.
Instead, as Stefánsson found with crosswords, our genes seem to influence our natural inclinations to do certain activities. What really dictates whether we have any capacity for them are factors such as whether we receive instruction and other opportunities at an early age, and our own willingness to practice, develop and move on.
The latter points to where genetics can exert its greatest influence on our life paths – our personality traits. According to Danielle Dick, a psychiatry professor at Rutgers University in New Jersey and author of the book The Child Code, most personality dimensions such as how extroverted or introverted, honestly, pleasant, impulsivelyand perhaps even how creative we, have some sort of genetic component.
“This reflects the fact that our genes influence the way our brain works, which affects how we think and interact with the world,” Dick said. “Some people have brains that are more inclined to seek out exciting or novel experiences, are more likely to take risks, or are attracted to more immediate rewards.”
There can be advantages to all of these traits. Businessmen, CEOs, fighter pilots, and athletes who compete in extreme sports all tend to be naturally ambitious. But having this genetic background can also come with certain costs. Risk-takers are more likely to develop addictionswhile Stefánsson’s work has shown that a proportion of people have genetics that would otherwise encourage creative thinking actually goes on to have schizophrenia. Impulsive people by nature can be better decision makers and ready to take advantage of opportunities that would otherwise pass them by, but they can also be vulnerable to developing gambling problems, dropping out of school o get fired.