Dna Analysis : Dna Profiling

In McClure, Weisburd and Wilson (2008) summary article arguing that in addition to bench science, field experimentation involving forensic methods is key to assess the utility of various methods to solve crimes. The study reflected that there is a need for more research into many aspects of forensic science, criticizing the strength of scientific evidence that’s collected at a crime scene and interpretations of most forensic methods while omitting DNA testing. McClure et al’s (2008) explains that in sexual cases and homicides, the presence of DNA evidence actually increased the likelihood of prosecution and a conviction. According to the article “…the case of convictions, the odds-ratio for the presence of DNA evidence was 33.1 for sexual offenses and 23.1 for homicides” (McClure et al., 2008). Subsequently, the research shows that there was a consistent gradual decline in the national homicide rates that began in the 1900s and continued through into the 21st century. The decline of homicides in the US has dropped by from more than 90% in the 1960s to 62% in 2003. Even though this significant drop has occurred during the introduction of the new DNA testing

Human DNA is very similar to one another, but only about 0.1% is different from the next person. That 0.1% can tell a person’s eye color, hair color, and other physical features. DNA analyst are able to take a drop of blood, the size of a dime, and duplicate the number DNA found in that drop. With the ability to duplicate DNA, analysts can have a back-up, in the event a human error were to occur. Analyst can tell you exactly where your ancestors came from and the percentage that is still inside your DNA. DNA is a very powerful tool that can identify a murder if the individual left any blood, saliva, skin tissue, hair or semen. The education needed to be able make use of the DNA consists of a great deal of science classes.

With over three million base pairs in the human gene, forensic scientists are able to distinguish a person’s genetic makeup.

I. Before the 1980’s, courts relied on testimony and eyewitness accounts as a main source of evidence. Notoriously unreliable, these techniques have since faded away to the stunning reliability of DNA forensics.

Beginning in the mid-1980s, the development of DNA analysis technology has revolutionised the field of forensic science within the criminal justice system. As the refinement of procedures and technology continues, even minute samples of biological material (including blood, saliva, semen and skin cells) are able to be analysed and used to link or acquit perpetrators of crimes. (Whitney, R n.d.)

Basically, our DNA (deoxyribonucleic acid) is our genes, and every person, except for twins, are born with a different DNA profile and that is in a giant database, containing every DNA profile of every person in the world. DNA testing started in 1985 by scientist Alec Jeffreys and was first used to solve a crime a year later. Before 1985 DNA evidence could not be used in court because it wasn’t invented yet, this increased the number of wrongful convictions which would have been prevented using DNA analysis. However, DNA analysis can still be used to solve crimes that occurred prior to the invention of DNA analysis, with a sufficient amount of DNA to be analyzed of course, which is a very small amount. Only a small amount of DNA is needed to find out who it belongs to, it can be found in blood, saliva, finger residue, hair, skin, semen and more.

Due to the uniqueness of DNA it has become a powerful tool in criminal investigations

DNA forensics can also narrow down suspect pools, exonerate innocent suspects, and link crimes together if the same DNA is found at both scenes. However, without existing suspects, a DNA profile cannot direct an investigation because current knowledge of genotype-phenotype relation is too vague for DNA phenotyping. For example, a profile from a first time offender that has no match in any database may give the information that the criminal is a left handed male of medium stature with red hair and freckles. It would be impossible to interview every man who fits that description. However, with available suspects, DNA forensics has many advantages over other forms of evidence. One is the longevity of DNA. Although it will deteriorate if exposed to sunlight, it can remain intact for centuries under proper conditions (Sachs, 2004). Because DNA is so durable, investigators can reopen old cases to reexamine evidence.

DNA profiles are very useful as although 99.9% of human DNA sequences are the same in every person, there is also enough DNA present which is different; this allows you to be able to distinguish one individual from another. This is the case for everyone apart from monozygotic twins. (Joseph Wambaugh)

DNA profiling can also be used to compare the DNA of a mother, her child, and the purported father can settle a question of paternity. An example is when DNA profiling proved that Thomas Jefferson or a close relative father a child of a slave named

Perhaps the most critical improvement in criminal examination since the happening to one of a kind finger impression ID is the usage of DNA development to convict punks or get rid of persons as suspects. DNA examinations on spit, skin tissue, blood, hair, and semen can now be reliably used to association guilty parties to wrongdoings. Dynamically recognized in the midst of the past 10 years, DNA development is in the blink of an eye by and large used by police, prosecutors, shield course, and courts in the United

Many times when a person is raped they are too traumatized to actually remember the full details or only remember certain characteristics, or facial features of the person who hurt them. So law enforcement makes an arrest based on the victims memory. Then after convicted it is found out that the wrong person was

There have been many incidents where cases have needed a solid prosecution in order to convict the defendant in a murder or rape case. This is where DNA Testing comes in to help. By taking a DNA test, a person can be found guilty or not guilty. If a person claims they have been raped there can be a sperm sample taken from the suspect in order to prove that he is guilty or not. In addition, in a murder case there can be blood taken from the suspect so they can tell of his innocence. There are several ways to determine whether a person is guilty or not by this method. Many cases have begun to use this method saying that it is foolproof. People say this is the method of the future of crime

DNA evidence is extremely helpful in criminal trials not only because it can determine the guilt of a suspect, but also because it can keep innocent people from going to jail. The suspect must leave a sample of their DNA at the crime scene in order for testing to occur, but DNA can be found in the form of many things such as semen, blood, hair, saliva, or skin scrapings. According to Newsweek, "thousands of people have been convicted by DNA's nearly miraculous ability to search out suspects across space and time… hundreds of innocent people have also been freed, often after years behind bars, sometimes just short of the death chamber" (Adler ). Though some may think it is a waste of time to go

DNA fingerprinting is a scientific technology involving the extraction, replication and arrangement of strands of an organism’s DNA. This results in the formation of a genetically distinctive fingerprint that is unique to the organism which the DNA sample was originally extracted from. Because of the specificity of a DNA fingerprint, the application of this technology can have a substantial influence on many aspects of society. Accessibility to a DNA database allows for higher efficiency in forensic investigations, personal identification, maternal and paternal testing. The availability of a national database to police officers and forensic scientists would equate to increased productivity in investigations and prosecution of suspects in a