The study found that TV fans are much more likely to develop coronary artery disease.
Dutch geneticists have isolated more than a hundred different small mutations in human DNA that are associated with an increased tendency to sedentary and recumbent lifestyles, including watching TV. Their findings were published in the scientific journal Nature Communications.
“Our observations and genetic analysis once again confirm that the tendency to constantly watch TV significantly increases the likelihood of developing cardiac problems. Interestingly, we did not find such an addiction among people who spent a lot of time at the computer or driving a car,”the scientists write.
In recent years, geneticists have discovered hundreds of small variations in DNA that affect not only the development of severe genetic diseases, height, weight and level of intelligence, but also its character. Among them are regions of the genome, variations in which affect tenacity, a predisposition to risky decisions or alcoholism, the time of starting a family, and even a tendency to have a dog.
As a rule, individual variations in such DNA segments have a rather weak effect on the behavior of each individual, which is why specialists study and discover them using large-scale genomic databases, in the creation of which hundreds of thousands of volunteers are usually involved.
A group of geneticists led by Professor Pim van der Harst of the University of Groningen (Netherlands) used one of the largest projects of its kind, UK Biobank, to find gene variations that are associated with predisposition to different forms of sedentary life.
TV and genes
Promotional video:
400,000 people in the UK have donated their DNA for this project. In addition, they underwent a comprehensive physical examination, as well as several surveys in which they talked about their habits and physical activity. Dutch researchers used this information to test whether a sedentary lifestyle actually increases the likelihood of developing coronary heart disease.
To do this, scientists tried to find in the genomes from UK Biobank sets of small mutations that affect a person's tendency to a sedentary or recumbent lifestyle, as well as to their certain manifestations. They compared these data with the results of classical statistical studies that associate cardiac problems with low levels of physical activity.
After analyzing over 19 million small differences in gene design, biologists have identified 193 variations in 169 DNA regions that influenced the predisposition to a sedentary lifestyle. Most of them, over 150 mutations, were associated with watching TV, and the rest of the gene versions were associated with sitting at a computer or driving a car. All of them were associated with the work of the nervous system and the transmission of signals between neurons.
Subsequent analysis of these variations in the genome confirmed that excessive TV addiction did increase the likelihood of getting coronary heart disease. According to scientists, every extra hour and a half of watching TV increased the likelihood of developing it by 42%, regardless of whether this desire was due to the influence of genes or social factors.
Interestingly, this relationship was not observed in the case of working at a computer and driving a car. Scientists have not yet figured out why this is happening.
According to geneticists, this may be due to the fact that drivers and PC users are much less likely to sit still for a long time and not so often eat high-calorie and junk food.