For example, if one parent had type A blood with A and O alleles and another parent had type B blood with B and O alleles, they could potentially produce four children with four different blood types.

The rarest blood type is called Rhnull. Only around 1 in every 6 million people have Rhnull blood. Learn about other blood types and their compatibilities in this article.

Blood type is determined by the dominant alleles or receptors both parents pass on to their baby. Alleles are a pair of genes on chromosomes. Genes are the basic unit of heredity.

Ten alleles (five M and five N alleles) of the MN blood group system with normal antigenicity were found by sequencing the glycophorin A (GPA) gene. This study demonstrates the systematic ...

In 1901, biologist Karl Landsteiner made a landmark discovery: Human blood contains different types of groups. This finding led to a Nobel Prize and the eventual discovery of the four specific ...

Instead of blending and creating a third type, both alleles make both types of blood. This results in type AB blood. Heterozygous genes and disease. A mutated allele can cause genetic conditions.