DISEASES INFORMATIONS CORNER

DNA forensics is a special area of expertise within the broader area of forensic science that deals with genetic materials during the investigation of a crime. Those who specialize in DNA forensics assist law enforcement officials by locating evidence in the form of genetic material that can tie suspects to the scene of the crime. DNA forensics can also be used to clear suspects of any involvement in criminal activity.

Without the discovery of DNA, forensic scientists would never be able to solve thousands of crimes that depend largely on the evidence they can unravel. DNA stands for deoxyribonucleic acid and it contains the building blocks of all life. Vital information is contained within the chromosomes and this information is unique to each individual.

DNA evidence is collected from crime scenes as well as from suspects after the fact. DNA can be obtained from blood cells, semen, hair follicles and skin samples left behind at the crime scene. Suspects may be required to provide DNA samples against which this evidence is compared. In addition, there are also larges databases filled with DNA information that a computer can scan against collected evidence.

DNA has provided the same kind of quantum leap in forensic investigation that fingerprints provided over a century ago. While the chemical structure of DNA is the same for everyone, there are literally millions of differences in the sequence of what is known as base pairs. Using this information, forensic scientists are able to arrive at what they term DNA fingerprinting, which essentially allows them to determine whether two DNA samples come from the same person, people who are related, or people who have no relation to each other.

The history of DNA forensics traces only back to the 1980s. British geneticist Alec Jeffreys was the first to proposed the concept of DNA typing as well as DNA fingerprinting. The experiments on the repetition of DNA sequences conducted by Jeffreys revealed a technique that could be used to examine variations between people. From Jeffrey's original tests, modern day DNA forensics was born.

In the early days of DNA forensics following Jeffrey's breakthroughs, it could take up to six weeks just to derive a conventional DNA profile. Some DNA evidence took even longer to construct. Due to advances in computerized technology, however, digital analysis and categorization of DNA samples can be processed into a DNA profile in just a matter of days.

Although the use of DNA forensics gets the most headlines when used to capture murderers and rapists, the most common use of this technology, by far, is for paternity testing. DNA forensic science is capable of determining the father of a child in cases where fatherhood is dispute as well as to either prove or disprove family ties in immigration cases.