Forensics

In order to identify a matching DNA of an individual as a perpetrator, Forensics and found in the crime scene, forensic scientists will be able to use the DNA blood, semen, skin, saliva and hair. This process is not what is called an official DNA profiling, sometimes called “genetic fingerprint”. In DNA profiling, repetitive DNA, and the length of the variable portion of the short mini satellite and tandem repeats are compared among the people. Usually, to identify the matching DNA, this method is a method very reliable. If the scene is contaminated with DNA from more than one person, you may identification is complicated. DNA profiling was used in forensic science to be developed in 1984 by geneticist Sir Alec Jeffreys in the UK, to blame the Colin Pitchfork in the 1988 Enderby murder case first.

As well as the development of forensic science, forensics the ability to obtain a sample of genetic matching minutes of hair blood that led to the review of some cases, skin, and saliva now. If the evidence is disclosed, it is impossible scientifically during the initial investigation. When combined with the elimination of dangerous method dual in some places, in the previous studies, it may be the case where that was not able to provide sufficient evidence to convince the jury reopens It is possible to make. The accused person may be needed to provide DNA samples for the purpose of matching a serious crime. Obtained court match that claims to be cross-contamination of evidence is complete and the most obvious defense DNA. This led to strict procedures and thorough in order to handle the new cases of serious crime. DNA profiling is used to identify mass incidents, the victims of accidents. DNA profiling has been used to identify the normal mass war grave victim personal ID as a positive part of the body or body serious accident – family matching.

In addition, forensics uses DNA testing, referred to as genetic fingerprinting or DNA typing to, DNA profiling is a technique used by forensic scientists to assist the identification of individuals by DNA profiles, respectively. DNA profile is a series encrypted number that reflects the structure of human DNA which can be used as an identifier of the individual. DNA profiling should not be confused with the complete genome sequence. It is used, for example, criminal investigation and testing of the parent.

However, 99.9% of the human DNA sequence is the same for each, enough DNA, to distinguish it from another individual as long as they are not identical twins are different. DNA profiling using the repeated (the STR) tandem repeat variable, the so-called variable number (VNTRs), particularly short tandem repeat very (“repeat”) array. VNTR locus is very similar to between loved ones, but individual unrelated that it has been reported in 1984 by Alec Jeffreys Sir Leicester University the first same VNTRs.The DNA profiling technology and now England variable, as is highly likely is, it is the basis of the DNA database of several nations. The Jeffries, as a chemical company, was released commercially in 1987, Imperial Chemical Industries (ICI), genetic fingerprinting Dr. began blood test center in the UK.

The process begins with (usually referred to as the “reference sample”) DNA samples of individual. The most preferred method for collecting a reference sample so as to reduce the possibility of contamination, it is to use a buccal swab. (For example, a court order may be needed, or did not get) if not available, which collects a sample of tissue or fluid other suitable blood, saliva, semen, or from other methods From (biopsy or tissue banks sperm, for example) samples stored (toothbrushes, razors, etc. for example), or personal items may need to be used to. Samples obtained from (relative biological) blood as possible, it can provide an indication of the profile of the individual bones profiled previously. Thereafter, the reference samples are analyzed in order to use any of the numerous techniques to be described below, to establish a DNA profile of the individual. DNA profile is compared with the other samples to determine whether there is a genetic match.

Using the (STR) short tandem repeats in use today, the use of DNA profiling is based on the PCR. Polymorphic region, to use a highly are short repetitive DNA sequences (to the foundation 4 repetitive most commonly, but. Other lengths may be used for 3 to 5 bases) This method is independent of it is possible for the number of repeating units varies almost certainly people that may be used to distinguish unrelated parties to DSS. (Position on a chromosome) STR loci thereof is amplified using PCR with the target using sequence-specific primers. The separated result, the DNA fragments are detected by gel electrophoresis. Separation and detection, there are two general methods for gel electrophoresis and capillary electrophoresis (CE).

Each STR is polymorphic, but the number of alleles is very small. Typically, the STR alleles are shared in about 5 – 20% of the people. Power of STR analysis comes from seeing the STR loci at the same time. Model allele can be individually identified very accurately. Therefore, I will offer better tools for STR analysis, identification. STR in the area of ​​more than has been tested in the test it more sophisticated individual.