Historically, it’s been believed that both parents — mother and father — pass along their intelligence-related genes to each of their children. However, recent research featured in Psychology Spot is claiming that children get their smarts from their mothers.
But why? Women carry two X chromosomes, and X chromosomes house the genes that are linked to intelligence. Because of this, the publication states that children are two times more likely to obtain intelligence genes from their mother.
Clinical Psychologist, Dr. Keith Whitt confirms, “The Y chromosome in XY men has about a hundred genes, none of which seem to be involved with cognition—thinking, figuring, planning … The X chromosome has a thousand genes, and a bunch of them influence cognition.”
So in boys, the father passes along the Y chromosome, and the mother passes along the X. But what about when a father passes along his X chromosome to his daughter? The duplicate gene intelligence will be suppressed. Psychology Spot says that the gene coming from a father will be “deactivated.” Likewise, some duplicate traits from a mother’s genes may be suppressed by a father’s genome.
Of course, it’s important to remember that the environment in which a child grows up also plays a factor in long-term learning, thinking and cognitive function. Scientific American reports that genetics is responsible for only about 50% of a person’s cognitive ability, with external influences making up the rest.
For example, if a child possesses a high IQ, but falls ill with a serious disease, it can hamper their growth and development. Likewise, if a child has an extremely high IQ, but does not receive nurturing, coaching and supportive education from his or her parents, he or she may fall behind.
So if you consider yourself to be a smart cookie, go ahead and thank your mom. And if you’re a woman looking for a Y chromosome contributor, remember that the smarts can come from within.
[h/t: Good Housekeeping]