Now, sometimes we also have those traits that can have three or more different types of alleles for that particular trait. And in such a case, whenever we have a trait that contains three or more different types of alleles, that trait is said to have multiple alleles. And one particularly common example in which a trait has multiple alleles in humans is the human Abo blood group traits. So there are three different types of alleles. For the blood group traits, we have allele given by uppercase I with the A SuperScript. We have allele that is given by uppercase I with the B SuperScript, or we have lowercase I.