Dna Analysis
Dna Analysis
DNA analysis is the starting point for many molecular biology procedures. Through DNA analysis, scientists are able to determines the pattern of certain parts of the genetic DNA material that is unique to each person. Through DNA analysis, scientists can precisely distinguish one person from another and this information as we all know can be vital in more than one situation. Dna analysis is used in crime scene investigations and even in medicine.
DNA analysis involves isolating DNA from cells, then comparing and contrasting the sequences of component chemicals between individuals. The DNA pattern can be ascertained from a sample of skin, hair, blood, or semen. Although differences are minimal (only 0.1% between unrelated people), certain regions of DNA, known as hypervariable regions, are unique to individuals.
DNA analysis is also known as genetic fingerprinting or DNA profiling. Professor Alec Jeffreys was the first one to develop the technique, which is now approved and used as a means of legal identification. Britain was the first country to put the knowledge into official practice.
What the entire DNA analysis is based on, is the fact that although two different people can have a majority of their DNa sequence exactly the same, there will still be some highly variable repeat sequences called Variable Number Tandem Repeats (VNTRs). Hence, DNA profiling relies on those VNTRs to identify each person, because those parts are random enough that two unrelated humans are unlikely to have the same alleles.
The process of DNA analysis starts with extracting DNA from the cells in a sample of blood, saliva, semen, or other appropriate fluid or tissue. There are six different methods of analysing the DNA through a fingerprint - RFLP, PCR, STR, AmpFLP, Mitochondrial analysis, Y-chromosome analysis.
The United States of America currently maintain the largest DNA database in the world with more than 6 million records as of 2008. The idea is that when a match is made from a a National DNA Databank to link a crime scene, it's used as proof in court and this has helped a lot of investigations. Of course, there are certain considerations to be made when evaluating DNA evidence. Recently, there have been an increasing amount of cases where criminals planted fake DNA samples to mislead the investigators.
deCODE is a biopharmaceutical company working in the field of DNA analysis applying its discoveries in human genetics to develop diagnostics and drugs for common diseases. Through DNA-based diagnostic tests, the scientists at deCODE (http://www.decode.com/) are able to predict risk of type 2 diabetes, heart attack, atrial fibrillation/stroke, and prostate and breast cancer.
