View source for DNA Fingerprinting

== Introduction ==
DNA fingerprinting, also known as DNA profiling, is a method used by forensic scientists to identify individuals by characteristics of their DNA. A DNA profile is a small set of DNA variations that is very likely to be different in all unrelated individuals, thereby being as unique to individuals as are fingerprints (hence the name for the procedure). 

== History and Development ==
The process of DNA fingerprinting was first developed by the British geneticist [[Alec Jeffreys|Sir Alec Jeffreys]] in 1984, while he was working at the University of Leicester. Jeffreys discovered that certain regions of DNA contained DNA sequences that were repeated over and over again next to each other. He also discovered that the number of repeated sections present in a sample could differ from individual to individual, and that this variation could be used to identify individuals.

== Principles of DNA Fingerprinting ==
DNA fingerprinting is based on the analysis of certain DNA regions known as [[Minisatellite|minisatellites]] and [[Microsatellite|microsatellites]]. These regions are highly polymorphic, meaning they vary greatly from one individual to another, making them ideal for DNA fingerprinting. 

[[Image:Detail-75103.jpg|thumb|center|A close-up image of a DNA sample on a glass slide.|class=only_on_mobile]]
[[Image:Detail-75104.jpg|thumb|center|A close-up image of a DNA sample on a glass slide.|class=only_on_desktop]]

== Techniques ==
There are several techniques used in DNA fingerprinting, including Restriction Fragment Length Polymorphism (RFLP), Polymerase Chain Reaction (PCR), Short Tandem Repeats (STR) analysis, and Amplified Fragment Length Polymorphism (AFLP).

=== Restriction Fragment Length Polymorphism (RFLP) ===
RFLP was the first method used for DNA fingerprinting. It involves the use of restriction enzymes to cut the DNA at specific sites, producing fragments of varying lengths. These fragments are then separated by size using gel electrophoresis, and the pattern of fragments is used to create a DNA fingerprint.

=== Polymerase Chain Reaction (PCR) ===
PCR is a technique used to amplify a single or a few copies of a piece of DNA across several orders of magnitude, generating thousands to millions of copies of a particular DNA sequence. This technique is often used in DNA fingerprinting to amplify the regions of DNA that will be analyzed.

=== Short Tandem Repeats (STR) Analysis ===
STR analysis involves the examination of specific regions (loci) within the DNA that contain short sequences of base pairs that are repeated. The number of repeats at each locus is highly variable from person to person, making this method very effective for DNA fingerprinting.

=== Amplified Fragment Length Polymorphism (AFLP) ===
AFLP is a PCR-based tool used in genetics research, mutation detection and genetic fingerprinting. AFLP generates a large number of DNA fragments for comparison, providing a detailed DNA fingerprint.

== Applications ==
DNA fingerprinting has a wide range of applications, from criminal investigations and paternity testing to genetic research and biodiversity studies.

=== Forensic Science ===
In [[Forensic Science|forensic science]], DNA fingerprinting is used to identify suspects or victims in a criminal investigation. It can also be used to identify human remains in cases where they are too degraded for standard identification methods.

=== Paternity Testing ===
DNA fingerprinting is commonly used in [[Paternity Testing|paternity testing]] to determine if two individuals are biologically parent and child. A child inherits half of their DNA from each parent, so their DNA profile should be a combination of their parents' profiles.

=== Genetic Research ===
In [[Genetic Research|genetic research]], DNA fingerprinting can be used to study the genetic diversity of a population or species. It can also be used to study patterns of inheritance and genetic diseases.

=== Biodiversity Studies ===
In biodiversity studies, DNA fingerprinting can be used to identify and catalog species, as well as to study the genetic diversity within and between species.

== Limitations and Ethical Considerations ==
While DNA fingerprinting is a powerful tool, it also has limitations and raises ethical considerations. For example, the technique requires a high quality DNA sample, and can be confounded by contamination or degradation of the sample. Ethically, the use of DNA fingerprinting raises concerns about privacy and the potential for misuse of genetic information.

== See Also ==
* [[Genetic Variation]]
* [[Human Genome Project]]
* [[Molecular Biology]]
* [[Genetic Engineering]]

[[Category:Genetics]]
[[Category:Forensic Science]]
[[Category:Biotechnology]]