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An allele is a variant form of a gene. Each gene resides at a specific locus (location on a chromosome) in two copies; one copy of the gene is inherited from each parent. The copies, however, are not necessarily identical. When the copies of a gene differ from each other, they are known as alleles. A given gene may have multiple different alleles, but only two alleles are present at the gene’s locus in any individual. (Read more HERE.)

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