Principles of Forensic DNA
for Officers of the Court
Principles of Forensic DNA for Officers of the Court
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Module 2 :: Biology of DNA

Topic 1 :: Biological Terminology

Locus and Allele

A locus (or loci, plural) is the actual location of the gene on a region of a chromosome.

An allele is a different form of a gene at a particular locus. The designation of two alleles at a particular locus is a genotype.

Click here to view an animation about genes and loci.

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