BY MORTEN BUSCH Sex chromosomes usually determine whether you are female or male. Women are XX. Men are XY. However, genetically, a few women are actually men. They grow up as women with a woman’s body, and most only discover well into puberty that they are different. Danish researchers map for the first time how many women are genetically men. The proportion was higher than expected. You cannot see it if you do not know what you are looking for. One in 15,000 males is born and grows up as a gir...