Cracking Our Dna Barcode Analysis

This paper examines Carrell et al’s research along with three other scholarly research articles to better understand the effects that the DNA recovered from a crime scene has on a particular case and the forensic science community.

Nowadays, DNA is a crucial component of a crime scene investigation, used to both to identify perpetrators from crime scenes and to determine a suspect’s guilt or innocence (Butler, 2005). The method of constructing a distinctive “fingerprint” from an individual’s DNA was first described by Alec Jeffreys in 1985. He discovered regions of repetitions of nucleotides inherent in DNA strands that differed from person to person (now known as variable number of tandem repeats, or VNTRs), and developed a technique to adjust the length variation into a definitive identity marker (Butler, 2005). Since then, DNA fingerprinting has been refined to be an indispensible source of evidence, expanded into multiple methods befitting different types of DNA

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

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.)

DNA testing is a critical and accurate tool in linking accused and even convicted criminals for crimes, and should be widely used to assess guilt or innocence before jail sentences are imposed. It was started up by scientists Francis C. Crick and James D, Watson in 1953 as they had described the uses, structures and purpose of the DNA “deoxyribonucleic acid” genetic fingerprint that contains organism information about an individual (testing

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

DNA’s certainty is dramatized in today’s society, which gives lay people the impression that DNA is infallible; however, in the case of Wayne Butler and others, the fallibility of DNA is exposed. Wayne Butler was accused of sadistically murdering Natasha Douty who was found beaten to death on Brampton Island in 1983. Wayne Butler was vacationing on Brampton Island during the timeframe of the murder; however, claimed to be jogging during this time. After submitting a blood test, Butler was eliminated as a suspect. However, Butler was arrested in 2001 for this murder because semen, which was found on the towel at the crime scene, was found to be a match. The John Tonge Centre performed a DNA test on the evidence on the towel. Butler was found innocent after it was identified that the John Tonge Centre mislabeled the test tubes containing the crime scene evidence. (“DNA Evidence”) This case proves that DNA testing may not be as reliable as we think.

Before the 1980s, 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. In 1984, British geneticist Alec Jeffreys of the University of Leicester discovered an interesting new marker in the human genome. Most DNA information is the same in every human, but the junk code between genes is unique to every person. Junk DNA used for investigative purposes can be found in blood, saliva, perspiration, sexual fluid, skin tissue, bone marrow, dental pulp, and hair follicles (Butler, 2011). By analyzing this junk code, Jeffreys found certain sequences of 10 to 100 base pairs repeated multiple times. These tandem

DNA is considered an individuals genetic fingerprint, thus it is exclusive to each and every individual. Since this exclusivity exists, DNA is a tool used for identification purposes. It has been utilized for investigations of serious crimes, identification of individuals killed in mass disasters, wars and paternity uncertainties1. Since the inception of the use of DNA in the 1980’s thousands of criminals have been caught and prosecuted with the help of DNA evidence2. Additionally, countless victims of mass disasters have been identified through DNA and returned to their loved ones. Although, there are various benefits to employing DNA it does not come without a sundry of ethical and legal concerns. The ethical concerns that have presented themselves are questions involving scientific reliability, DNA evidence in court, human rights, and finally the other uses of the DNA database.

Due to the brief period that Hodge had been allowed to see her attacker, the prosecution felt that stronger evidence was needed to prove a connection. The brief 6-second glimpse that the victim Nancy Hodge obtained during her ordeal wasn’t considered viable enough for trial purposes (Lewis). This relatively new forensic investigation technic involving the use of DNA fingerprinting was in its infancy and was pioneered by a British scientist might hold the answer to convicting the rapist.

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 profiling technologies have had a considerable impact on how forensic science and criminal investigation have been understood, carried out, and regulated in the last 25 years. Current methods of forensic DNA profiling (known also as DNA fingerprinting and DNA typing), based on Polymerase Chain Reaction (PCR) amplifications of a varying number of Short Tandem Repeat (STR) loci found at different locations on the human genome, are regularly described as constituting the “gold standard for identification” in contemporary society. Prior to the implementation of PCR based extraction and amplification methods in the 1990’s, the initial uses of DNA fingerprinting (based on Multiple and Single Locus Probes) were largely confined to reactive

DNA fingerprinting was discovered by Professor Sir Alec Jeffreys from the University of Leicster. After spending time studying molecular biology in Amsterdam with Dick Flavell, Jeffreys moved to the university and set out to “marry the new

This quote shows that DNA fingerprinting is a pretty accurate way of finding a suspect as it is almost impossible, given the odds of 1 in 64 billion, for two people who are not related to have DNA that would match up. The DNA would probably have to be contaminated for two unrelated people to have the same DNA, or even DNA that is similar enough to confuse suspects. This is one of the reasons that DNA fingerprinting is so useful. It is incredibly accurate as a form of identification as the genetic make-up of a person cannot lie. The results from DNA are pretty binary in terms of identification.

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