While techniques to identify a suspect of his genetic code exist since the 1980s, DNA analysis has gained in popularity in recent years. On the one hand, television shows like "csi: Crime Scene Investigation" has increased public awareness of the Forensics and DNA analysis through the use of the technology, as determine size of particles and synthesizers DNA analyzers that collect and analyze DNA. So intriguing and compelling are instances that today many juries expect DNA evidence in the courtroom.
The truth is, the DNA is probably the biggest promotion in police work from analysis of fingerprints. This breakthrough in genetic technology translates not only current criminals to justice, it has also helped break cases unresolved for years.
What is DNA?
DNA means deoxyribonucleic acid and it hereditary material in humans and almost all other organizations. Almost every cell in the body of the person has the same DNA and it contains information used daily in the growth and metabolism and it influences most of our features.
A DNA molecule is a long string known as a double-helix twist. In human cells, DNA is tightly wrapped in 23 chromosomes where one member of each pair of chromosomes from your mother and your father. Simply put, your DNA is a combination of your mother and father and DNA except if you have a twin, your DNA is unique for you.
DNA collection
DNA can be collected on virtually anywhere. Even a criminal wearing gloves may unwittingly leave traces of biological material such as hair, blood, semen, skin, or even sweat. Some cells are all that are needed to get enough DNA information to identify a suspect.
DNA analysis techniques
1 Restricted Fragment Length Polymorphism analysis
One of the first methods used forensic was RFLP, analysis that analyzes the lengths of strands of DNA, including base pairs called, variable number tandem repeat them here. In this method, investigators must dissolve DNA in an enzyme that breaks down the strand to specific points. The number of repetitions affects the length of each strand of DNA and investigators compare samples by comparing the length of strands. RFLP analysis requires a broad sample of DNA was contaminated with dirt.
Today, several laboratories are alternate RFLP analysis short Tandem repeat (STR) analysis, a method which offers several advantages, the greater is its ability to start with a much smaller sample of DNA.
2. The analysis Y marker of
While most laboratories use methods of RFLP or STR analysis, there are situations that require a different approach. For example, in a situation as a sexual assault case when there are several contributors of genetic material, analysis of Y-marker males can resolve the mixture and untangle exactly what men were involved. This technique looks at several genetic markers on chromosome Y. Given that chromosome is passed from father to all her sons, DNA on chromosome is can be used to identify different male DNA.
3 Mitochondrial DNA (mtDNA) analysis
RFLP and STR testing can be used over ancient remains or lack of biological evidence of nucleated cells. In such situations, the mitochondrial DNA analysis is used. This method uses the DNA of mitochondria in a cell and is particularly useful in solving cold cases.
4 Single Nucleotide Polymorphism (SNP) analysis
The SNP analysis is a relatively new technique, and it is useful in cases where forensic laboratories are presented with highly degraded DNA samples. Scientists are analyzing DNA variations where one nucleotide replaces another. This genetic modification is called a unique polymorphism and it is an excellent marker, which can determine the sensitivity of the person to certain diseases.
Solving Crimes
There are two ways that DNA analysis can be done to solve crimes. In cases where the perpetrator has been identified, DNA samples can be taken by the suspect and compared with genetic evidence found at the scene of the crime. If the samples match after testing, the suspect can be loaded.
The second method is used when no suspect has been identified. With the help of equipment and techniques such as laser diffraction, DNA can be detected and recovered from the scene of the crime. Under controlled conditions, evidence of DNA sample is analyzed and compared the DNA of offender profiles database. A match to identify the perpetrator of the crime.
This article is amazing as it helps to solve the through the dna tests . It helps in finding the right person who had committed the crime.
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