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

Nuclear DNA

Nuclear DNA is packaged into chromosomes within the nucleus of a cell. Nucleated cells contain 23 pairs of chromosomes (46 total) — half inherited from each parent.

Notable exception: Each individual sperm contains only 23 chromosomes. Forensic scientists look at multiple sperm, which collectively provide the full complement of 46 chromosomes.

Click here to view an animation about how a child inherits genes from its parents.

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