Intelligence is inherited from the mother, reveals science

The intelligence is one of the most recurrent topics in Psychology and Mind. In addition to having a whole section devoted to various monographs, investigations and theories about intelligence, today we echo a particularly interesting topic.

Intelligence: is it inherited ... from the mother?

People who are lucky enough to be smarter than the average should start thanking someone else in particular: their mothers. And it is that, according to several investigations have highlighted, it seems that it is the mothers who transmit most of the genetic load related to cognitive abilities .

This would disprove many of the gender biases that remain deeply rooted in our societies and that have been cruelly accompanying women in particular for centuries. According to this information, the intelligence of the parent would not be a strong factor when it comes to predicting the intelligence of the children.

Conditioned genes, the key to everything

The scientific basis of this matter lies, precisely, in the existence of "conditioned genes". These genetic components, as described by the biologists who have studied them thoroughly, behave differently depending on whether they originate from a male or female body.

Apparently, these genes contain something like a biochemical label that provides information about their provenance , and that even reveals if these genes will be active or not in the cells of the child. In particular, some conditioned genes are only activated if they come from the mother. In case this same gene is inherited through the paternal route, it is not activated. As might be expected, there are other genes that work in reverse: that is, they are only activated if they come from the father.

Chromosome X, essential in the development of cognitive potential

It is well known that intelligence is inherited from parents to children, but there was no record until recently that this ability was due to a greater extent of one of the two parents. The different studies that have revealed that children have a greater probability of inheriting the mother's intelligence suggest that the genes related to cognitive abilities are located in the X chromosome .

In fact, the data that support this thesis come from afar. In 1984, a study at the University of Cambridge already detected the trend. The team of researchers analyzed certain biochemical and genetic components of the brain, and concluded that the genes of the mother provide more information for the development of brain structures associated with thinking and mental operations.

To arrive at this surprising finding, the researchers worked with embryos of mice modified to reproduce, only, the genes of the mother or those of the father. However, when the scientists moved the embryos to the uterus of a female mouse so they could continue to develop, they died.

In this way, the researchers realized that there are conditioned genes that only activate when they are inherited by the mother, and that are essential for the development and survival of the embryo. With the embryos that were genetic copies of the parents something different happened: their genes were crucial for the growth of the placental tissues. They also died.

The hypothesis was clear: if those genes in particular were so highly essential for the development (and survival) of the embryo, it would be reasonable to think that they would be genes with great responsibilities in the organic functioning of animals and humans, and could perhaps keep a strong relationship with certain brain functions. A hypothesis that, after successive studies isolating variables, was validated.

Mice with surprisingly large heads

Mice that had a higher proportion of maternal genes developed an abnormally large brain, and yet their body was very small. In contrast, mice with paternal genes had a tiny head and overdeveloped body.

As the scientists were detecting which genes were coming from the mother and which from the father, In turn, they identified several cells that only contained maternal or paternal genes in different brain areas that govern different functions and cognitive processes, such as intelligence or memory.

Scientists did not find any paternal cells in the cerebral cortex, where the structures are located that allow us to have complex cognitive functions, such as intelligence, decision making, language and other abilities.

New investigations and evidences

Over the years, the scientific community has been reviewing this curious genetic phenomenon.In fact, one of the most reputable researchers in the field of intelligence, Robert Lehrke, revealed that most of the intellectual capacity of neonates is generated on the X chromosome. He was able to demonstrate, even, that women are twice as likely to inherit traits linked to intelligence , having twice that same 'X' chromosome.

A few months ago, another study by the German University of Ulm found that the genetic material involved in brain damage is closely linked to the X chromosome. They also pointed out that one of the evidences of this is the fact that mental and intellectual disabilities are 30% more frequent in men.

IQ Predictor

All the previous studies are very interesting and give specific keys to the relationship between the genes of the mother and intelligence. However, one of the most revealing studies is the longitudinal analysis carried out in the Medical Research Council Social and Public Health Sciences Unit from the USA

Over a long period of time, 12,000 young people between the ages of 13 and 22 were interviewed annually. Analyzing different variables about individuals, such as skin color or sociocultural and economic level, they discovered that the indicator that best predicted the intelligence of each subject was C.I. from his mother .

Beyond genetics

But not only genetics gives us data on this issue. There is other research that shows that the mother plays a fundamental role in the intellectual and cognitive development of children, through day-to-day stimuli. Several studies suggest that addiction , that bond of pristine confidence with the mother, is closely related to future intelligence.

Attachment and its importance for the development of intelligence

Several investigations at the University of North Carolina, among many others, found that children who successfully develop a secure attachment to their mothers are able to carry out more complex symbolic play . In addition, they are more consistent and have more tolerance for frustration.

It seems that secure attachment offers the basis for children to grow confident in their possibilities, facing the challenges to strive and solve the problems of their day to day. It is also remarkable that the mothers who provide this secure attachment are also those who stimulate their children more and better so that they can advance in their cognitive development.

What percentage of intelligence is inherited?

But is intelligence really inherited? In what proportion is this? It is often said that between 45 and 55% of intelligence is written in the genes . This gives us to understand that there is also a significant part, approximately half, that develops if the family, social and personal conditions are good.

And it is important to remember that intelligence is nothing other than the ability of human beings to solve problems. There is no specific area of ​​the brain responsible for solving problems, but it is our entire brain that works globally to address any task that requires an effort of our cognitive abilities. In addition, for more imbroglio, we not only use rational thinking for these purposes, but also heuristic thinking, intuition and emotions, which are usually related to the genetic inheritance of the father, come into play.

Stimulate the child's intelligence

Do not pay excessive attention to C.I. of a son Intelligence is an extremely complex construct, which develops if the child's mind is stimulated conveniently, with challenges and tasks that, little by little, force him to climb in his stages of cognitive development.

As parents, we must be able to understand that we can contribute a lot to make our children mature and they are developing more complex cognitive skills, and this must be done, let's not forget, attending to the emotional and playful needs of the little ones in the house. Everything helps.

You may be interested: "5 tips to nourish your child with emotional intelligence"

Bibliographic references:

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• Matas, L .; Arend, R. A. & Sroufe, L. A. (1978) Continuity of adaptation in the second year The relationship between quahty of attachment and later competence. Child Development; 49: 547-556.
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