The M and N factors are glycoproteins on the surface of red blood cells.

The M and N factors are glycoproteins on the surface of red blood cells. Unlike other types of red blood cell antigens, the M and N factors do not cause antibody reactions in human blood transfusions. People with type M blood are homozygous for the M allele, and people with type N blood are homozygous for the N allele. Heterozygous individuals have type MN blood. In a study of a population of Inuit living in the Northwest Territories, 640 people had blood type M, 320 had blood type MN, and 40 had blood type N. Calculate the frequency of the genotypes in the population studied. Show all steps to your solutions.

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