According to a new report, the DNA profile of your husband or wife influences everything from how much you eat beef or fatty fish to how much time you spend watching TV.
Researchers at the University of Edinburgh have discovered that in a pair, the genes of the female partner have more effect on the actions of her partner than the other way around.
The results, published in the Nature Human Behavior journal, are based on a theory known as indirect genetic effects (IGEs).
This means that the genotype – or genetic profile – of one person influences the measurable characteristics of another person with whom the environment is shared.
For so-called vertical relationships, such as between a parent and his or her child, evidence for IGEs has already been given.
‘Stunning’ DNA research shows how genes make Covid life-threatening and harmless for some for others.
For instance, the genes of a mother can influence the birth weight of her infant, and the genetic makeup of parents has been related to the cognitive ability and educational achievement of their offspring, although these are not specifically heritable traits.
Less research has been done on “horizontal” IGEs, such as between long-term partners, but some studies have already found proof of the trend in relation to educational achievement among groups of school mates.
Professor Albert Tenesa, lead author of the study and chair of quantitative genetics at the Roslin Institute, said that the phenomenon is based on how people’s own genetic predispositions affect their actions, such as focus, and thus the risks or benefits that people around them will encounter.
He said, “I may not smoke, but if all my family around me are smokers and genes determine part of their smoking behavior, those genes affect how much smoke is in the household, and that affects my risk of lung cancer.”
Also, if the class is a good class in which the children are well-behaved and reasonably intelligent, there is a good possibility that everyone has a good environment in which their genes work better, impacting the group’s educational level.
In animals, this has also been seen. If you place a really violent animal in an enclosure, it affects the whole nature of how the others act.
The aggressiveness is partly due to the genes of the species, but that affects who eats first, how they act, how they interact with each other, and that also happens in humans.
“If someone is depressed at home, that changes the whole dynamic.”
Self-harm and attack deaths in Scotland rose by 20% in the first six months of the pandemic.
Prof. Tenesa and colleagues decided to find out how much the genotype of an individual would influence the characteristics and behaviors of their partner.
They studied DNA samples stored in the U.K. from 80,889 heterosexual couples of European descent. Biobank and compared them with questionnaires on self-completed health and lifestyle that covered everything from diet and mood swings to the amount of hours they slept and smoking habits each night.
In this way, data related to 105 complex characteristics could be obtained by the researchers.
On average, they found that 1.5 percent of the variation in 51 measurable traits was explained by a partner’s genotype, although this value was greater for some attributes such as mental wellbeing, eating patterns, and level of education.
Of these 51 characteristics, 13 characteristics were correlated with “consistent evidence”: body fat percentage, ease of skin tanning, dried fruit intake, frequency of eating oily fish, frequency of eating beef, lamb/lamb meat, time spent watching TV, smoking status, number of siblings, self-reported astigmatism, level of education, mood fluctuations, and being upset.
They note that for six features mainly related to diet and obesity, such as grain intake, beef consumption frequency, or waist-to-hip ratio, the “female-to-male effect was significantly larger than the male-to-female effect”
The researchers added that the “biggest challenge” is to distinguish how much of the characteristics are directly triggered by genes within a pair and how much is due to “assortative mating” – in other words, that attracts like that.
There is a tendency for individuals to select someone who is more like them,