How many alleles determine someone’s blood type
Biology · Middle School · Mon Jan 18 2021
Answered on
Explanation: The four main blood groups A, B, AB, and O are controlled by three alleles: A, B, and O. As humans are diploid, only two of these can be present in any one genotype.
Everyone inherits two alleles of the gene, one from each parent. The combination of your two alleles determines your blood type.
There are two special blood types when it comes to blood transfusions. People with type O blood are universal donors because there are no molecules on the surface of the red blood cells that can trigger an immune response. People with type AB blood are universal recipients because they do not have any antibodies that will recognize type A or B surface molecules.