Panda blood (meaning Rh-negative blood) is passed from parent to parent. Rh blood type is the most commonly used blood grouping system other than ABO blood type, which is mainly determined by the presence or absence of the D blood group antigen on human red blood cells. Generally, the absence of this antigen indicates Rh-negative blood, while the presence of this antigen indicates Rh-positive blood, in which the proportion of people carrying Rh-negative blood is relatively small, and therefore relatively rare. Rh blood type is passed on to the next generation through the autosomes, with Rh-negative being a recessive gene and Rh-positive being a dominant gene. If both parents are Rh-negative, 100% of their children will be Rh-negative.