- Rh Negative Facts
April 19, 20210
An evolutionary oddity
Nobody knows why Rh-negative blood is as common as it is. It doesn’t produce any obvious advantage in people who have it but it can create a disease called hemolytic disease in the fetus and newborns. That can happen when the mother has rh-negative blood, the baby in her womb has rh-positive blood, and the mother previously had a baby with Rh-positive blood.
Because babies with hemolytic disease can die, natural selection ought to cause Rh-negative genes to become less common and eventually disappear. But that hasn’t happened and no one knows why.
Thanks to Mike at: https://www.rhesusnegative.net