A boy and a girl with different skin colors were born a few months ago. The children were born at Dewsbury County Hospital, West Yorkshire
Leo was born first, weighing 2 kg 660 grams, followed by his sister Hope, weighing 2 kg 800 grams. Their mother says: “I knew that I would have twins, I knew that they were a boy and a girl, but I could not assume that they would have different skin colors.” Obviously, the baby only inherited “white” genes, her brother is only black. This case is unique - the probability of occurrence of twins with different skin colors in a mixed pair is 1 case per 1 million people.
Scientists believe that seven different genes determine skin color. If a woman is of mixed race, then her eggs contain a set of genes that code for white and black skin color. The man has the same thing. When the egg is fertilized, the mixed genes are passed on to the child.
Very rarely, eggs and sperm can contain genes that code for the same skin color. If the egg and sperm contain only genes that code for white skin, then the baby will be white, and vice versa. For a mixed race couple, the probability of such an event is 100/1.