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​DNA Fingerprinting

updated: June 29, 2022

Definition

DNA fingerprinting is a laboratory technique used to determine the probable identity of a person based on the nucleotide sequences of certain regions of human DNA that are unique to individuals. DNA fingerprinting is used in a variety of situations, such as criminal investigations, other forensic purposes and paternity testing. In these situations, one aims to “match” two DNA fingerprints with one another, such as a DNA sample from a known person and one from an unknown person.

 DNA-fingerprinting


Narration

There are various methods for analyzing DNA to establish if two samples are the same or different. This is sometimes referred to as DNA fingerprinting. For example, two cloned pieces of DNA can be studied in the laboratory to determine if they have portions in common, and thus overlap with one another. In a different setting, such as a crime scene, DNA samples can be collected and analyzed to determine if they match DNA samples obtained from suspects of that crime. If two DNA samples have the same fingerprint, then there is a very high statistical likelihood that they came from the same person. Such an approach can also be used to establish paternity.