Does the IQ of a son really follow his mother’s?

The IQ of a son is not entirely determined by the mother's genetics, but is the result of the combined effects of the parents' genes. The inheritance of IQ is regulated by multiple genes, and is also significantly affected by factors such as education, nutrition, and environment.

From a genetic perspective, human IQ-related genes are distributed on multiple chromosomes, among which the X chromosome carries some cognitive function-related genes. Because men inherit the X chromosome from their mothers, some studies believe that mothers may have a slightly higher impact on their sons’ IQ than fathers. However, IQ-related genes on autosomal chromosomes also come from both parents, and epigenetic modifications can lead to differences in gene expression. Nutritional status during pregnancy, especially the intake levels of folic acid and DHA, may affect fetal neurodevelopment, while environmental factors such as early education quality and family cultural atmosphere often play a greater role in children's intellectual development than genetic differences.

There are certain X-linked genetic diseases such as fragile X syndrome that may affect male intellectual development. In these special cases, the mother is indeed the carrier of the disease gene. However, the genetic mechanism of differences in general intelligence is complex, and there is currently no sufficient evidence to support the decisive role of mother's genes in her son's IQ. Twin studies show that even if identical twins are raised separately, the correlation of IQ is still significantly higher than that of fraternal twins, which confirms the basic role of genetics, but acquired factors can cause IQ fluctuations of 10-15 points.

During preparation for pregnancy, both parties should maintain a healthy lifestyle and avoid exposure to teratogens. Children need to pay attention to balanced nutritional supplements during their growth stage, especially foods rich in omega-3 fatty acids, zinc, and iron. Create a rich cognitive stimulation environment and promote the development of synapses through parent-child reading, thinking games, etc. Regular developmental assessment and timely intervention if cognitive delays are found are more practical than focusing too much on genetic factors.