The IQ is very important for every human being, and every parent would like to have a child with high IQ score. You may find many articles saying that the intelligence comes from the mother, but are they true?
According to these articles, the intelligence is a result of the female X chromosome, which has over 1,000 genes, and many of them influence the perception level. However, these statements are simply not true, genetics is not a simple field of research, and every single body cell has a pair of chromosomes, X and Y. The chromosome is a thread-like formation that has protein and nucleic acids, which transfer and store genetic information. The cognitive abilities do not come solely from the mother’s side.
So, if it is inherited through the X chromosome, both parents contribute to its formation. The mother contributes an X chromosome, but the father contributes either a Y chromosome or an X chromosome. Yes, the females carry 2 X chromosomes and the men carry 1 X and 1 Y chromosome, but this does not mean that the mother transfers the gene of intelligence. Namely, the genetic property of gender-specific genes is either deactivated or activated, depending on the specific selection and genetic characteristics. The deactivated genes do not influence the genetic development, and the activated genes do. If the characteristic of the mother is more dominant the paternal genes are deactivated, and vice versa, which gene will be activated and deactivated is a pure chance.
The 2 X chromosomes in the women led the belief that the intelligence is transferred by the mother’s side. But, these two X chromosomes in mothers are not identical since one of them has been obtained from their fathers. This means that the chances of inheriting a specific characteristic are not automatic just because the mother has two X chromosomes.
The doubled “gene dosage” in people with two or more chromosomes works like this: each cell turns off most of one X or the other. This means that an X-linked variant might not be used since some cells may shut it down.
Intelligence is not that simple and it is not always a result of the genes as the environmental factors take role in its creation. If the half of it is being inherited, the other part comes from many genetic variants scattered across our genomes that operate together in many different ways.
The inherited genes are subjected to numerous environmental factors having an impact on their creation throughout the life. So, we cannot state that the intelligence comes only from our genes or mother’s X chromosome, it is much more complex and it is interplay of gene variants and environment.
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