What is the only way to have offspring with type AB blood

A father who is blood type AB could pass either an A or a B allele to his son or daughter. This couple could have children of either blood type A (O from mother and A from father) or blood type B (O from mother and B from father).of the blood type gene: A, B, and O. Every person has two copies of their blood type gene: one from mom and one from dad. Usually, the only way to have type AB blood is to have one copy of the A version and one copy of the B version.

Explanation:

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