DNA fingerprinting
DNA fingerprinting is a test to ID and evaluate the genetic information-called DNA in a persons life. DNA fingerprinting procedure.You first obtain a sample of cells, such as skin, hair, or blood cells, which contain DNA. The DNA is extracted from the cells and purified.
DNA fingerprinting is a test to identify and evaluate the genetic information-called DNA (deoxyribonucleic acid)-in a person's cells. It is called a "fingerprint" because it is very unlikely that any two people would have exactly the same DNA information, in the same way that it is very unlikely that any two people would have exactly the same physical fingerprint. The test is used to determine whether a family relationship exists between two people, to identify organisms causing a disease, and to solve crimes. Only a small sample of cells is needed for DNA fingerprinting. A drop of blood or the root of a hair contains enough DNA for testing. Semen, hair, or skin scrapings are often used in criminal investigations . A person who has DNA fingerprinting done voluntarily usually provides a sample of blood taken from a vein. DNA testing also can be done on cells obtained by a simple mouthwash or a swab of the cheeks inside the mouth, but these methods are not recommended.
Procedure
The procedure for creating a DNA fingerprinting consists of the first obtaining a sample of cells, such as skin, hair, or blood, which contain DNA. The DNA is extracted from the cells and purified.
Technique
DNA fingerprinting is a laboratory technique used to establish a link between biological evidence and a suspect in a criminal investigation. RFLP stands for restriction fragment length polymorphism In this method, DNA is extracted from a sample and cut into segments using special restriction enzymes. RFLP focuses on segments that contain sequences of repeated DNA bases, which vary widely from person to person. The segments are separated using a laboratory technique called electrophoresis, which sorts the fragments by length. Only a small sample of cells is needed for DNA fingerprinting. A drop of blood or the root of a hair contains enough DNA for testing. Semen, hair, or skin scrapings are often used in criminal investigations.
The Positive Side
DNA can help find out who a person's parents or siblings are. Prenatal paternity tests are available to mothers who need to identify the father of their unborn babies. DNA left at the scene of a crime can be matched with a sample from a suspect. This method is helpful in gathering evidences used in criminal trial and can be used to convict guilty and acquit the innocent. DNA fingerprinting provides medical professionals with information needed to determine hereditary diseases. This method also helps patients prevent the disease through lifestyle changes and intervention. This also offers peace of mind for parents and other individuals seeking for identity. DNA fingerprinting makes establishment of relationship and identification lot easier. This method is also very versatile, flexible and efficient. Even with just a small drop, identity can easily be established The great advantages of DNA profiling also lies in its specificity. Even relatively minute quantities of DNA at a crime scene can yield sufficient material for anaylsis. Forensic scientist typically compare at least 13 markers from the DNA in two samples. In a test with 13 markers, the probability that any two individuals would have identical profiles is estimated to be below 1 in 10 billion.
The Negative Side
The accuracy and efficiency of DNA fingerprinting solely depend on competency of equipment, lab personnel and experience. This method can degrade as time passes by and this would result to inaccurate result and information. Inaccurate result can also put an innocent person to jail or to other complicated situation. There is also a possibility of discrimination. The prevalence and resilience of DNA can inundate crime scenes with excessive DNA especially in public places like bars or restrooms. Human error also plays ab big part in confusion and labeling. Consequently, when specimens are collected properly and the procedure is performed correctly, DNA profiling is an extremely accurate way specimens are to compare a suspect's DNA with crime scene specimens.DNA evidence is the only one of many types of evidence jurors should take into account when considering a case. TV shows like "CSI" may have popularized forensic science to the point where some jurors have unrealistic expectations of DNA analysis and accord to more weight than other types of evidence. This phenomenon is sometimes called "CSI effect." Maintaining DNA databanks can help police identify criminals, but it can also pose ethical quadaries when authorities keep samples from people who have never been accused of crime. DNA dragnets, operations where police collect samples from large number of people in a geographic region to find a culprit, have especially controversial.