If both parents are Rh-positive but carry one Rh-negative allele, there's a 25% chance they could have an Rh-negative child.

However, a child can have a different blood type to both of their parents, depending on which genes they inherit. Each parent passes one allele (gene) for blood type to their child. A parent who ...

Indeed, "codominance" is the specific term for a system in which an allele from each ... in the human ABO blood group system. Many blood proteins contribute to blood type (Stratton, 1952), and ...