DNA Fingerprinting *
Are you interested in the technical and ethical aspects of genetic screening, forensic science, and DNA fingerprinting? Scientists use different forms of a gene, called alleles, to differentiate between two fingerprints. One such sequence used in human DNA fingerprinting is the Alu repeat (a 300 base pair repetitive sequence of DNA) on chromosome 16. During evolutionary time, up to 1 million copies of the Alu repeat have become randomly inserted throughout the human genome. Within a specific region on chromosome 16 called PV92, some of us carry an Alu repeat and some of us do not. Such small variations among individuals' genotypes are inherited. These variations are the raw material for natural selection and evolution. These subtle variations in our DNA also provide evidence about our ancestry and form the basis of personal identification via DNA fingerprinting.
An example of DNA fingerprinting is shown in Figure 1. You can investigate your own DNA fingerprint, and that of family members, using a Human Alu DNA Extraction and Amplification kit from our partners at Carolina Biological and basic biotechnology techniques like PCR (polymerase chain reaction) and gel electrophoresis. Which alleles are present in your family? Can you test a larger group of people and study population genetics? Do the alleles differ according to ancestry?
Figure 1. This is an example of DNA fingerprinting made by staining DNA on a gel. (Photo courtesy of Bio-Rad Laboratories, Inc.)
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Last edit date: 2018-10-17
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