Applications

DNA typing can be used in forensic cases of murder, rape, homicide, and other violent crimes. DNA samples are typically taken during a criminal investigation, from the crime scene area or from the victims clothing or body and include: blood, hair, skin cells, or any other genetic material. The samples are then compared using VNTR patterns to determine a match either to the suspect or victim. VNTR patterns can also be used to identify victims of homicide when a sample from the parents is available. If the sample is extremely small PCR can be used to amplify the DNA for the typing tests.

Commonly used to determine specific breeds of some horses and dogs. This DNA fingerprint can be used for registering animals and establishing pedigree as well as for parentage verification. DNA identity information can be used to correlate EPDs to parent stock which allows selection of animals that meet set criteria for performance.

Can be used to solve crimes against wildlife such as illegal hunting, trafficking in endangered species, and the production and sale of products made from illegally hunted animals. There is one lab in the world that deals with these cases, The National Fish and Wildlife Forensics Laboratory in Ashland, Oregon. They work on cases from the 50 United States and from 155 other countries worldwide. The lab staffs 33 people that work on approximately 900 cases every year. They have a reference warehouse that holds stuffed animals and animal parts used to identify creatures. They have nearly 5,000 complete animals and over 30,000 blood and tissue samples, mostly donated from zoos around the world after an animal dies. They use DNA in 15-20% of their cases to link animals and their human killers to a crime scene. In combination with ballistic evidence and fingerprints they have become very accurate at tracking illegal hunters and poachers. In one example a man returned home after an illegal hunt and washed and dried his clothes at home. The lab was able to use animal hairs found in the dryer’s lint holder to place him at the crime scene. They can also use barely visible bloodstains on clothing to track hunters down years later, and with absolute statistical certainty.

Helpful when trying to discover if an animal that has been found is really an endangered species or only a mutant of another species.

Used especially for agricultural identification. Many of the crops currently grown in the United States contain genes that were introduced in order to develop a new type of crop. They can be detected in the crop using PCR. Approximately 50-75% of produce and processed foods in grocery stores in the United States are genetically modified or contain genetically modified organisms.

Done with PCR, using primers specific to certain disease strains can test for pathogens like e. coli or mad cow disease in food such as hamburger meat.

DNA paternity testing is the most accurate way, with 99.9% certainty, to determine paternity. It can be used for maternity testing also but that is quite uncommon because mothers usually give birth at a hospital or with others that can testify to her being the mother. (Example: maternity testing could be used on a child that was born at home and then anonymously left at an orphanage or hospital.) Such accurate testing is possible because a person inherits VNTR patterns from their parents, and every persons DNA is unique except for that in identical twins. VNTR patterns are extremely specific and can be accurately compared. A child will share one band with the biological mother and one with the biological father. They can be used for parent identification as well as biological parenthood in adoption cases.

This application of DNA fingerprinting has been discussed but is not in use at the current time. It would involve using the VNTR patterns of individuals as a type of genetic bar code to identify them. This is relatively impractical because it would be far too expensive and time consuming to analyze and store millions of VNTR patterns to be used as personal identification references.

These alligator snapping turtles were recovered in 2002 in Greenwood, Mississippi, in a sting operation that ended in the arrest of a seller.

Confiscated animal products, including tusks, tortoise shells, and stuffed birds, at the U.S. Fish and Wildlife National Forensics Lab.

Ringed by his handiwork, Cornell researcher Bruce Reisch examines the leaves of a Chardonnay grapevine for signs of fungal disease.

A slide representing 20,000 tomato genes is projected onto Mark D’Ascenzo, a researcher at Boyce Thompson Institute for Plant Research in Ithaca, New York. Scientists there are trying to identify the genes that make certain tomatoes resistant to diseases. "We’ve isolated hundreds of genes that are interesting candidates," D’Ascenzo says, "but we’re still years away from understanding the whole picture." Once scientists do, the genes that are responsible for resistance can be synthesized and inserted into a new generation of tomato plants.

Applications of DNA fingerprinting/typing