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2025: Sensational scientific explanation for why men are superior to women

A group of geneticists from USA found that about 23% of the difference in height between men and women was explained by differences in the activity of the SHOX gene located on the sex chromosomes. The results of the study, published May 19, 2025 in the scientific journal PNAS, reveal the genetic mechanism behind one of the most notable physiological differences between the sexes.

Scientists analyzed the genomic structure of almost 928,000 adult men and women from three large biobanks - UK BioBank, MyCode and All of Us. Of particular value for the study were data from 1.2 thousand volunteers with an unusual configuration of sex chromosomes, including carriers of Klinefelter syndrome and Jacobs syndrome.

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Фото: Freepik

Geisinger Medical Center Associate Professor Matthew Etiens and colleagues established that the SHOX gene is present on both the female X chromosome and the male Y chromosome. However, in women, the level of activity of this gene in one of the two X chromosomes turned out to be slightly lower than in the Y chromosome in men.

The researchers revealed that each additional Y chromosome contributed to an increase in average growth of 3 cm more compared to the additional X chromosome. This difference in the effect of sex chromosomes on growth is due to the peculiarities of the activity of the SHOX gene, which plays an important role in regulating the growth program.

The SHOX gene is located in the pseudoautosomal region at the ends of the X and Y chromosomes. When the scientists compared the growth of people with different chromosomal abnormalities, they found that having an extra Y chromosome provided more growth gain than having an extra X chromosome, regardless of the influence of male hormones.

Genetics specialist Matthew Etiens explained the biochemical mechanism of this phenomenon: in women, most of the genes on one of the two X chromosomes are inactivated, but the genes at the very tip of the X chromosome remain active. The SHOX gene is close enough to this tip, leading to its incomplete suppression. In men, both the X chromosome with the SHOX gene and the Y chromosome with the same gene are active.^[1]

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