[ad_1]
Throughout history, humanity has been eager to prolong its life; In this regard, many surveys suggest that the secret of longevity lies in the genetic makeup. However, recent research suggests that genetics play a less important role in the duration of life than previously thought.
Indeed, previous studies did not take into account the selection patterns of human partners. In this way, it is possible that previous surveys overestimated the heritability of longevity.
Longevity depends on other factors, in addition to genetics
Variations between individuals are due to genetic or environmental factors; in particular, heritability is defined as the proportion of variation in biological factors in a group of people that can be attributed to the genetic variation of individuals. In other words, heritability is a measure of the extent to which the presence of a trait can be explained in a group of people, depending on their genetic configuration. thus, not all characteristics of an organism are due to environmental factors such as diet or lifestyle.
Since longevity usually occurs in specific family groups, several studies have estimated that the lifespan is determined, at least 30%, by genes. However, a recent study suggests that the role of genetics on longevity is less important than previously thought.
To reach this conclusion, the researchers took into account the data of more than 400 million people who shared their information in the Ancestry database. Taking into account that the focus was the length of useful life, the information was taken into account for people born in the 19th century or early 20th century who have already died.
In doing so, longevity between brothers and sisters and first cousins was compared, giving results similar to those of previous surveys; that is, it was observed that the life span had between 20 and 30% of heritability. However, by performing a finer analysis of the data, patterns were found that caught the attention of the researchers.
Assortment and longevity
One particular case that has attracted attention is that longevity of spouses tends to be similar; This could be explained by the fact that couples share similar environments, such as diet, lifestyle and eating habits; it influences the duration of life. In addition, it was observed that political brothers and sisters had a similar longevity, even though they did not share their environment and were not related to blood.
In view of the results, the researchers studied the influence of a process called assortment of assortments; The matching assortment is a phenomenon from which people choose romantic partners with qualities similar to theirs. In this sense, when this factor has been taken into account, the heritability of longevity has fallen to 7%.
This does not mean that people choose their partners based on the length of life, it would be impossible; it puts on the table the influence of other factors that go beyond genetics.
One of these elements could be the availability of economic resources; People often become linked to other people of the same social class, which could be related to the length of life, so as to look for better opportunities to have a healthy lifestyle, the # 39 access to health services, increased education, among others.
Finally, researchers warn that this does not imply that genes do not influence the duration of life; therefore, it is suggested that further research be done taking into account the genetic characteristics of individuals as well as the above factors.
Reference: Estimates of the heritability of human longevity are greatly inflated due to the easing of mating, (2018). https://doi.org/10.1534/genetics.118.301613
Source link
