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

Rules of DNA

The four-letter DNA alphabet of C, G, T, and A always follows certain rules. Bases can only pair together in a specific way: C only bonds to G, and T only bonds to A.

C-G
G-C
T-A
A-T

The specific combination of these bases through chemical bonds is known as base pairing.

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