Our DNA does far more than dictate eye color or height; it also pulls the strings behind many everyday quirks. In this roundup of 10 things surprisingly controlled by our genes, we’ll explore how genetics steer our cravings, finances, fears, sleep, shopping habits, fidelity, relationships, musical talent, victory gestures, and even whether our armpits stink.
10 Things Surprisingly: The Genetic Pull Behind Our Sweet Tooth
10 Fats And Sugar
Our so‑called “thrifty genes” are hard‑wired to nudge us toward fatty, sugary foods, making obesity a tough battle to win. Back when our ancestors were hunter‑gatherers, three regular meals were a luxury; many didn’t know when—or if—the next bite would arrive.
Early humans quickly learned that high‑fat and high‑sugar fare supplied long‑lasting energy. Fat packs more calories per gram than other nutrients and is lighter to store, while sugar converts easily into fat, giving a sustained fuel source.
Those with thrifty genes survived famines because they could hoard energy when food was scarce. Over millennia, the genes persisted, leaving most of us with a built‑in sweet tooth and a penchant for calorie‑dense foods.
9 Spending And Investment
Researchers Stephan Siegel and Henrik Cronqvist uncovered that our DNA helps shape how we spend, save, and invest. By studying 15,000 twin pairs, they found strikingly similar financial habits even when the twins lived apart.
According to their findings, family upbringing steers our money behavior until roughly age 25, after which our genes start to assert influence, especially around age 40, nudging us toward particular risk tolerances and portfolio choices.
The study showed that genetically‑influenced risk appetite affects whether we diversify our holdings. While some twins gravitated toward a handful of stocks—potentially risky—they also tended to chase previously successful equities, reflecting a genetic bias toward familiar wins.
Additional work by Hersh Shefrin suggests that only about a quarter of people carry a “thrifty” gene that curbs spending, while the majority possess variants that predispose them to higher expenditure.
8 Fear Of Snakes And Spiders
Even infants display an instinctive wariness of crawling critters. In two experiments, six‑month‑old babies showed heightened stress when shown images of snakes or spiders, yet remained calm when viewing pictures of fish or flowers.
Joshua New and Tamsin German of Columbia University found that 252 adults could quickly spot a spider in distorted images, underscoring an innate detection ability likely forged because venomous arachnids and serpents posed lethal threats to early humans.
While many modern spiders are harmless, ancient ancestors faced highly venomous species capable of delivering fatal bites or debilitating toxins. Those lacking the genetic sensitivity to these creatures often fell victim, leading to the preservation of fear‑related genes. Some scholars, like Jon May, argue that cultural factors—such as the unsettling appearance of spiders—also play a role.
7 Sleep
The average adult needs about seven hours of nightly rest; dropping below six typically triggers fatigue, impaired cognition, and mood disturbances. However, a distinct subset of people thrives on far less sleep thanks to a variant called p.Tyr362His, nicknamed the “Thatcher gene” after the former British Prime Minister famed for sleeping only a few hours.
In a twin study involving 100 pairs, researchers discovered that carriers of this gene maintained sharp mental performance despite chronic sleep restriction, whereas non‑carriers showed noticeable declines in alertness and cognitive function.
This genetic advantage appears to allow the brain to operate efficiently on reduced rest, challenging the conventional wisdom that everyone requires the same amount of shut‑eye.
6 Shopping
While “shopping” is often stereotyped as a female domain, Geoffrey Miller of University College London argues that men are genetically primed to purchase. Male shoppers are motivated by the desire to signal wealth and attractiveness to potential mates.
In prehistoric times, men adorned themselves with animal pelts and body paint to impress women. As societies evolved, the same drive transferred to clothing, automobiles, and other status symbols, turning material displays into evolutionary courtship tools.
Today, many men cease lavish gifting once a relationship is secured, shifting the burden of appearance to women. This dynamic helps explain why women appear to shop more often, even though the underlying genetic impulse originates in men.
5 Infidelity
In 2010, Justin Garcia and his team at Binghamton University identified a link between a specific DRD4 gene variant and a higher propensity for cheating. The study surveyed 181 men about their sexual histories and then analyzed their DNA.
Men carrying this DRD4 variant showed a statistically significant tendency to cheat, even without obvious external motivators. The researchers suggest the gene influences dopamine pathways, prompting a heightened need for rewarding experiences.
Critics like Robert Weiss caution that the sample size was modest and that environmental factors—such as personal values and life circumstances—also shape fidelity, urging a more nuanced interpretation.
4 Relationships
Researchers at Peking University pinpointed the C‑1019G variant of the 5‑HT1A gene as a factor that nudges individuals toward singleness. In a cohort of 579 Chinese university students, only 40 % of those with the gene were in a romantic partnership.
The gene appears to foster moodiness, anxiety, and a generally gloomy outlook, traits that can deter people from pursuing or maintaining relationships. Parallel work also links lower oxytocin levels—a “bonding hormone”—to reduced sociability, further supporting a genetic basis for relationship choices.
3 Music
While early theories posited that early exposure to music hones talent, a study of 568 British female twins suggests genetics play a decisive role. Participants listened to 26 familiar tunes—such as “God Save the Queen,” “Yankee Doodle,” and “Happy Birthday”—each containing deliberate errors.
One in four twins failed to spot the mistakes, yet when an identical twin detected an error, their sibling was far more likely to notice it as well. In contrast, fraternal twins showed no such concordance, underscoring a hereditary component to musical perception.
2 Victory Sign
The triumphant “V” hand sign, along with accompanying body language—raised arms, expanded chest, and a lifted head—appears to be hard‑wired. Earlier assumptions labeled these gestures as learned, but observations at the 2004 Paralympic Games revealed that blind athletes, who had never seen anyone else perform the sign, instinctively displayed it after winning.
Conversely, after losing, these athletes slumped their shoulders and concealed their faces, mirroring the behavior of sighted competitors. Researchers infer that such expressive patterns were ingrained in our genes by ancient ancestors who used body language to signal dominance or submission.
1 Smelly Armpits
About 98 % of people experience a distinct odor when they perspire, but a rare 2 % remain odor‑free thanks to the ABCC11 gene. Researchers at the University of Bristol examined 6,495 women and identified only 117 carriers of this variant.
The gene was originally linked to dry earwax, a trait prevalent among East Asian populations. The ABCC11 variant reduces the production of certain amino acids in sweat, limiting bacterial growth and thereby diminishing odor.
Even among those with the gene, many still opt for deodorant, suggesting cultural habits often trump genetic advantage.