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Principles of Forensic DNA for Officers of the Court

ABO Typing

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photo of a test tube filled with blood
National Institute of Justice (NIJ) (see reuse policy).

Discovered in 1901 by Karl Landsteiner, the ABO system and its subsequent introduction into forensic science was just as remarkable in its day as DNA typing is today.

Although the ABO system was used to differentiate individuals, it did not have a high degree of discriminating power. Of the four possible groups: A, B, AB, and O - approximately 45% of the population has type O blood.

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