🩺 Investigating the XY factor

[phkrause]

Illustration: Shoshana Gordon/Axios

Scientists are beginning to understand how sex chromosomes and hormones affect people's risk for certain diseases — and whether the biology behind those differences can be harnessed to improve treatments. Why it matters: Doctors and scientists have long recognized certain diseases affect men and women differently, but that is rarely reflected in the dosage and design of drugs, Axios managing editor Alison Snyder writes. 💼 Case in point: A newly approved drug for Alzheimer's disease may be less effective for women — who are more likely to develop the disease over their lifetime — than men 🖼️ The big picture: Study after study has described the differences in the impact of disease between males and females. In the U.S., 80% of people who have an autoimmune disease are female. Rheumatoid arthritis, Hashimoto's disease, and multiple sclerosis all affect women more than men. Men are more likely to develop severe COVID, but emerging evidence suggests long COVID is more common among women. Nearly two-thirds of people 65+ in the U.S. with Alzheimer's disease are women. 🔬 Researchers are starting to understand the molecular underpinnings of these differences. One study found a gene on the X chromosome is expressed more in the immune cells of females than in males. When researchers deleted the gene in mice bred to have an autoimmune disease similar to MS, they had fewer symptoms. Read on.