WHY ARE MEN TALLER THAN WOMEN?
Alexander S. F. Berry et. al., PNAS, May 19, 2025
• The study published May 19 in the Proceedings of the National Academy of Sciences was drawn from genetic data from roughly 1 million people, from three large biobanks in the U.S. and the U.K.
• They found that people with an extra Y chromosome were taller than those with an extra X chromosome. That suggests the SHOX gene, which appears on both the X and Y chromosomes, has a stronger effect when it’s on the Y.
• Here’s why: In women, who have two X chromosomes, one is mostly inactive and the SHOX gene is only partly active. In men, who have one X and one Y, both versions of the SHOX gene are fully active.
• In other words, the gene gives men a bigger boost, researchers say.
• That slightly larger gene effect explains about one-quarter of the average height difference between men and women. • The rest of the height difference likely comes from other genes and from male sex hormones, Oetjens added.
