Imagine being a little kid, about 5 years old, staring in the mirror and viscerally realizing that you’re alone in your difference. Not only are you alone, but the only thing in your world that looks ...

A new study in the British Journal of Sports Medicine found that transgender women maintain physical advantages in strength and heart and lung capacity years after transitioning. The Brazilian study ...

Some physical traits that differ between sexes are known to be linked to certain single nucleotide polymorphisms (SNPs) in chromosomes other than the X and Y chromosomes, with each SNP representing a ...