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Principles of Forensic DNA for Officers of the Court

Heterozygous versus Homozygous

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A person's pair of alleles at a particular locus (genotype) is either homozygous or heterozygous .

If a person has two alleles at a locus that are indistinguishable, the person is homozygous at that genetic location.

Likewise, if two alleles are different at one locus, the person is heterozygous at that genetic location.

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