Although long-lived in families, genetics has much less impact on life expectancy than previously mentioned, according to a new analysis of the total family tree of more than 400 million people.
The study shows that the inheritance of life is well below historical estimates that did not take into account our tendency to choose partners with similar characteristics.
"Maybe we could learn a lot about the biology of aging from the genetics of man, but if the heritability of life is low, it refines our expectations about what kind of things we can learn and how easy it will be," said Graham Ruby, the head of society Calico Life Sciences – American Society for Research and Development.
"It helps to contextualize issues that aging researchers can effectively ask," she added
Heritability measures how long a lifetime can be explained by genetic differences, without differences, such as lifestyle, sociocultural factors and disasters.
While preliminary estimates of the life span of human life ranged from about 15 to 30%, the new study is probably no more than seven percent, possibly even lower.
In a study published in the journal Genetics, the team used an online genealogy resource with public family trees created by the client, which represents six billion ancestors.
Removing redundant entries and those who still lived, the remaining intertwined thighs involved more than 400 million people, mostly Americans of European origin.
Each of them was linked to another by the relationship of the parent or spouse's wife.
They focused on relatives born in the 19th and early 20th centuries and found that the life span of the spouses is usually related, more like the ones in the siblings and sisters of the opposite sex.
When comparing different types of genera, it was found that brothers and bornes are primarily the interlinked life span, although they are not blood relatives and do not even share households at all.
The researchers found that the sister of the brother sibling or sister of his spouse and sister had a similar lifetime that there was something else.
The answer can be in an asortative mating. People often choose partners with similar characteristics – in this case, how long they live, they explained.