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Principles of Forensic DNA for Officers of the Court

Coding Versus Noncoding Regions

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DNA has coding and noncoding regions. Coding regions are responsible for making proteins and are often called genes. Noncoding regions are those pieces of DNA between the coding regions that do not make any known proteins.

Approximately 95% of a person's DNA is made up of noncoding DNA which is sometimes nicknamed "junk DNA" because it does not code for any physical characteristics or proteins. The name "junk" does not imply unreliability for identification testing.

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