What is an allele and what does it do

An allele is one of two, or more, forms of a given gene. E.g. the ABO blood grouping is controlled by the ABO gene which has six common alleles. Nearly every living human's phenotype for the ABO gene is some combination of just these six alleles.

Explanation:

well we can't tell you because we cant see the time give a screen shot or something.

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