A new study by Israeli researchers found that a man cannot become a woman by simply “identifying” as one and vice versa. Geneticists from Israel’s Weizmann Institute of Science discovered certain genes that are only expressed in women, while others are only expressed in men. Professor Shmuel Pietrokovski and Dr. Moran Gershoni studied 20,000 genes, sorting them by sex, and searching for differences in expression in each tissue.

They eventually found around “6,500 genes with activity that was biased toward one sex or the other in at least one tissue, adding to the already major biological differences between men and women.” Some of the biggest differences were in genes responsible for body hair, fat storage, muscle building, and milk production for breastfeeding. The researchers also found that biological sex also plays a role in preventing specific illnesses. READ MORE