Explanation: Women not only live longer than men, they also appear to be in more robust health. A new hypothesis offers a reason why: it's in their genes. Women are known to have a lower incidence of cancer — men have a two- to five-fold greater risk of developing the disease.
The X chromosome is known to contain a number of genes related to health, Fish said, and adding microRNAs to the mix would suggest that the X chromosome is even more important in terms of health differences between men and women.
However, the X chromosome is far from the only reason for the strong immune response in females, Fish said. Hormonal differences and a number of other factors probably play a role, she said.