A recent article published by The Independent, explored the possibility of intelligence being more likely to be inherited from the mother than the father.
Genetic research from several studies suggests that a large number of the genes responsible for intelligence come from a category of “conditioned genes.” When inherited, conditioned genes can be deactivated if they are come from the wrong parent. In the case of intelligence, these genes are deactivated when inherited from the father and activated when they come from the mother.
Another study explored the possibility that intelligence is more prevalent on the X chromosome and therefore is twice as likely to be transmitted from the mother as she possesses two X chromosomes.
One study used genetically modified mice to map the spread of different genes across the body. They found cells with active paternal genes were not as common in the cerebral cortex, where functions such as reason and language occur, which are considered some of the most advanced cognitive functions.
Glasgow University disputed that mice were a good model for human intelligence and decided to test the theory that intelligence is inherited from the mother on a study of 12,686 young people of 14-22 years old. The team did a series of IQ tests on the participants, and found that the IQ of the mother was more similar to the IQ of the child than the IQ of the father was.
However, the university did stress that the intelligence of this group was equally dependent upon environmental factors, including race and socio-economic status that left some more advantaged than others. Other environmental factors included the level of education reached by both the child and their parents. Memory training was also considered; information can be moved from short term memory to long term memory through revision and tutorage, which effectively makes people “smarter” in exams.
‘All factors combined, research does show that nurture and environmental factors are just as important as nature and genetics.’
The University of Washington also suggested a secure emotional bond between a mother and child is crucial for the growth of some parts of the brain. Researchers analysed the relationships between a group of mothers and children over 7 years and found that children identifying strong bonds had a 10% larger hippocampus by 13 years old than those who had mothers that were physically and emotionally distanced. However, this debate about nurture and emotional bond with a child can also be fulfilled by the role of the father in the absence of the mother. All factors combined, research does show that nurture and environmental factors are just as important as nature and genetics.