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Recently, the internet has been filled with various content claiming that children’s intelligence is completely inherited from their mothers. There is also quite a bit of content that states that fathers have almost no role in the inheritance of intelligence. This claim was usually linked to the X chromosome, then simplified to the conclusion that the intelligence gene came from the mother.
At first glance, this statement sounds scientific because it uses the term genetics. However, if we look deeper, this conclusion turns out to be inconsistent with modern scientific evidence. Geneticists actually show that intelligence is a very complex trait. There is no single gene that determines intelligence, especially if it only comes from one parent.
In other words, the assumption that a child’s intelligence is only inherited by the mother’s genes is a form of misinformation about health. Correct information is much more interesting and more complex than simply blaming or praising one parent.
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Intelligence Is Not Controlled by One Gene
The first thing to understand is that intelligence is a polygenic trait (polygenic trait). This means that intelligence is influenced by thousands of gene variations that work simultaneously.
Large-scale research into genetics shows that there is no independent “intelligence gene.” Instead, there are thousands of DNA variations, each of which makes a very small contribution to thinking, memory, problem solving and other cognitive functions.
This is the reason why scientists are very careful when discussing the relationship between genes and intelligence. The real world is much more complicated than one-sentence social media narratives.
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Father and Mother Both Pass Genes to Children
Biologically, every human gets about 50 percent of their genetic material from their father and about 50 percent from their mother. This means that all autosomal chromosomes, namely the 22 pairs of chromosomes that are not sex chromosomes, come from both parents equally.
On these chromosomes there are many genes related to brain development, nervous system, metabolism, synapse formation, and memory function.
Because most of the genes that influence brain development are on autosomal chromosomes, fathers and mothers both contribute to a child’s intelligence potential.
To say that only the mother transmits intelligence is to ignore basic facts about the inheritance of human genes.
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Why did the myth emerge that intelligence genes come from the mother?
This myth largely comes from a simplification of the results of old research on the X chromosome.
It is true that the X chromosome carries more genes than the Y chromosome. Some of the genes on the X chromosome are also related to brain development. Because boys only have one X chromosome that comes from the mother, it is believed that intelligence must be inherited from the mother. The problem is, this logic is too simple.
First, genes related to brain function are not only on the X chromosome. Most of them are spread across various other chromosomes.
Second, women have two X chromosomes, but one of them undergoes a process called X-inactivationso that not all genes are active simultaneously.
Third, intelligence is influenced by thousands of genes spread throughout the human genome, not just on one chromosome.
Therefore, modern geneticists no longer support the claim that intelligence is inherited solely through the mother.
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Genes Provide Potential, Environment Shapes the Results
Another mistake that often arises is considering genes as absolute determinants. In fact, genes are more properly understood as conferring potential. This potential then develops according to the environment in which the child grows.
A child may have gene variations that support high learning abilities. However, if he experiences malnutrition, lack of sleep, rarely gets stimulation, or grows up in a stressful environment, this potential may not develop optimally.
On the other hand, children with ordinary genetic potential can develop very well if they receive a supportive environment.
Thus, the relationship between genes and the environment is not mutually exclusive, but complementary.
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Nutrition Plays a Big Role in Brain Development
The brain is an organ that requires a lot of energy, especially during growth.
Various studies show that adequate protein, iron, iodine, zinc, choline, vitamin B complex, omega-3 fatty acids, and various other micronutrients are very important for the development of the nervous system.
Children who experience chronic malnutrition are at risk of experiencing impaired cognitive development, even though they have good genetic potential.
This is why the mother’s health during pregnancy, breastfeeding, nutritious complementary foods, and the child’s diet are factors that should not be ignored.
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Education and Stimulation are Equally Important
The brain develops through experience. When children are asked to talk, read books, play, solve problems, draw, sing, or do simple creative activities, the neural networks in their brain continue to form new connections. The more often the brain is used for learning, the stronger the connections between nerve cells are formed.
On the other hand, lack of stimulation can hinder the development of thinking abilities.
This shows that intelligence is not just a gift from genes, but is the result of interactions between biological factors and life experiences.
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The Emotional Environment Also Shapes Learning Ability
Children who grow up in a loving environment generally have a better chance of thriving.
On the other hand, prolonged stress due to violence, neglect, family conflict, or psychological pressure can affect brain development.
Stress hormones such as cortisol that continue to increase for a long time can interfere with memory function, attention and learning ability.
Therefore, a safe, warm and supportive home atmosphere is one of the best investments for the development of children’s intelligence.
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Modern Genetics Uses the Concept of Polygenic Scores
Today, scientists study intelligence using much more sophisticated approaches than they did just a few decades ago.
Through research genome-wide association studies(GWAS), scientists compare millions of DNA variations from hundreds of thousands to millions of people.
The results show that no one gene has a dominant influence. Instead, thousands of small gene variations work together to shape a person’s cognitive abilities.
This approach is known as polygenic score. Even though it can estimate some variations in cognitive abilities, this score is still unable to predict a person’s intelligence perfectly because the influence of the environment is still very large.
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Don’t Blame Mom or Dad
One of the bad effects of this myth is the emergence of a habit of blaming each other. When a child experiences learning difficulties, some people immediately blame the mother because they are considered the source of the intelligence gene.
In fact, this assumption does not have a strong scientific basis at all. Both father and mother provide genetic material to the child. After the child is born, both of them also have an important role in providing an environment that supports their growth and development.
Thus, the success of children’s cognitive development is the result of cooperation between the whole family, not the responsibility of just one party.
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CONCLUSION
Modern genetics has shown that the assumption that a child’s intelligence is inherited by the mother’s genes is a false simplification and can be misleading.
In fact, both father and mother contribute genetic material that influences brain development. In addition, intelligence is not determined by one gene, but by thousands of genes working together. Even after genetic factors are taken into account, the environment still has a very large role in determining how this potential develops.
Good nutrition, adequate education, early stimulation, health, quality sleep, physical activity, warm emotional relationships, and a supportive learning environment are factors that have been proven to help the development of children’s cognitive abilities.
So, if one day you come across content stating that a child’s intelligence is only inherited by the mother, there’s no harm in being critical. Science is almost always more complicated than erroneous content on social media. And like many things in biology, the answer is not “only mother” or “only father”, but rather a combination of both which is also influenced by the environment in which a child grows and learns.
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SOURCE
Davies, G. et al. (2018). Study of 300,486 individuals identifies 148 independent genetic loci influencing general cognitive function. Nature Communications, 92098.
Deary, I. J. (2012). Intelligence. Annual Review of Psychology, 63453-482.
Plomin, R., & Deary, I. J. (2015). Genetics and intelligence differences: Five special findings. Molecular Psychiatry, 20(1)98-108.
Plomin, R., DeFries, J. C., Knopik, V. S., & Neiderhiser, J. M. (2016). Top 10 replicated findings from behavioral genetics. Perspectives on Psychological Science, 11(1)3-23.
National Human Genome Research Institute. (2024). Genetics and genomics. https://www.genome.gov
World Health Organization. (2020). Nurturing care for early childhood development: A framework for helping children survive and thrive to transform health and human potential. World Health Organization.
Center on the Developing Child at Harvard University. (2021). Brain architecture. Harvard University. https://developingchild.harvard.edu
