Females have one active X chromosome and one dormant X chromosome in each cell. But a study suggests that genes on the ...

The X and Y chromosomes, commonly referred to as the sex chromosomes, are one such pair. They determine the biological sex, reproductive organs, and sexual characteristics that develop in a person.

Researchers have shed new light on how a type of heart valve disease -- aortic valve stenosis -- progresses differently in males and females.

"You either have XX or XY chromosomes," Rep. Nancy Mace, R-S.C., wrote Feb. 20 on X. "Those are the options." Most commonly, a person is born with two X chromosomes (female) or an X and a Y (male).

Researchers found that a gene on the Y chromosome influences how aortic valve stenosis progresses differently in males and ...

So far, of the approximately 31,000 genes in the human genome, men and women differ only in the two sex chromosomes, X and Y, and only a few dozen genes seem to be involved. Moreover, it's now known ...

Human biology is not black and white. Although newborns are typically categorized as male or female at birth based on visible ...

Scientists discover that women's second X chromosome awakens later in life, expressing genes that protect the brain from ...

Females, on average, live nearly five years longer than males. They also tend to experience age-related cognitive decline at ...