The alleles in the ABO blood group system gives rise to 5 types of genotypes.

The correct answer is 'False'.

• Blood groups explained by Landsteiner involved the presence or absence of antigens (A and B) in the individual.
• Three allele model involves inclusion of the Rh factor along with A and B antigens.
• As a result, an offspring can obtain one out of the six various combinations of genotypes from the parents, which are as follows:

ABO	A	B	O
A	AA	AB	A
B	AB	BB	B
O	A	B	O