PCR (Polymerase Chain Reaction) is the quick and easy method of making unlimited copies of any fragment of DNA. Since it’s first introduction ten years ago, PCR has very quickly become an essential tool for “improving human health and human life (TPCR)”. Medical research and clinical medicine are profiting from PCR mainly in two areas: detection of infectious disease organisms, and detection of variations and mutations in genes, especially human genes. Because PCR can amplify unimaginably tiny amounts of DNA, even that from just one cell, “physicians and researchers can examine a single sperm or track down the elusive source of a puzzling infection” (TPCR)”. These PCR- based analyses are proving to be just as reliable as previous methods-sometimes more so and often much faster and cheaper.
Polymerase chain reaction (PCR) is a technique used “to amplify the number of copies a specific region of DNA (Brown)”, in order to produce enough DNA to be adequately tested. This technique can be used to identify with a very high-probability, disease-causing viruses, bacteria, a deceased person, a criminal suspect, and also in the event of an outbreak, “Real-Time PCR can effectively monitor the success of clean-up efforts (RAL,Inc)”.
In order to use PCR, one must already know the exact sequence of a gene or the sequence of interest that lie on both ends of the DNA. While similarity among genes of organisms exists, there will always be genes whose DNA sequences differ from each other. By identifying the genes that are different and unique, one can use this information to identify an organism.
DNA is a double-stranded, “consisting of two such nucleotide chains that wind around each other in the famous shape known as the double helix (TPCR)”. DNA consist of Adenine, Thymine, Cytosine, and Guanine components which can be arrange to generate a “sentence” of a gene sequence which can consists of either a few or thousands of letters long.
To get this copying process started, a template molecule of the DNA or RNA you want to copy is required along with two primer molecules that make up the strands of all genetic materials.
These primer molecules consists of about 20 letters long, which can be linked together in the order desired by a DNA-synthesizer “which add and link one letter at a time (Brown)” to generate the primers needed to start PCR.
There are three major steps in PCR that must be met in order for the process to be successful.
The adage is a symphony. The way the PCR method works is by first mixing a solution containing the DNA, DNA polymerase primers, and certain nucleotides.... ... middle of paper ... ...
PCR or polymerase chain reaction is not a DNA typing technique, but a variety of different DNA tests (Riley). PCR duplicates and increases the quantity of a DNA strand which is beneficial to forensic scientists who are faced with little quantity of materials (Saferstein 394). The introduction of PCR-based testing in DNA analysis required scientists to switch to smaller targets that had the same repetitive variation (Jones). This is how short tandem repeat, the newest method of DNA typing,
In order to do this a polymer of DNA “unzips” into its two strands, a coding strand (left strand) and a template strand (right strand). Nucleotides of a molecule known as mRNA (messenger RNA) then temporarily bonds to the template strand and join together in the same way as nucleotides of DNA. Messenger RNA has a similar structure to that of DNA only it is single stranded. Like DNA, mRNA is made up of nucleotides again consisting of a phosphate, a sugar, and an organic nitrogenous base. However, unlike in DNA, the sugar in a nucleotide of mRNA is different (Ribose) and the nitrogenous base Thymine is replaced by a new base found in RNA known as Uracil (U)3b and like Thymine can only bond to its complimentary base Adenine. As a result of how it bonds to the DNA’s template strand, the mRNA strand formed is almost identical to the coding strand of DNA apart from these
"Polymerase Chain Reaction (PCR) Fact Sheet." National Human Genome Research Institute. 10 Dec. 2007. National Institutes of Health. .
Cervical cancer tissues and normal cervical tissues were collected from 24 newly diagnosed patients with primary cervical cancer, in order to perform the experiments outlined in the paper. Experiments were also performed on the following human cervical carcinoma cell lines: HeLa, SiHa, C33A, and CaSki, which were purchased from a company. The researchers extracted the genomic DNA from the samples collected. The DNA was then bisulfite modified and amplified using PCR. The PCR product was then examined through gel electrophoresis to insure a single band was obtained, and then sequenced by Invitrogen. Methylation-specific PCR was then carried out of the bisulfate-treated DNA. This was done to check the consistency of the ...
Polymerase Chain reaction (PCR) is used to isolate a predetermined strand of DNA on the double helix. Once the desired DNA is isolated it is able to be copied as much as needed (2). In this experiment PCR was used to isoloate Vangl2 from Zebra fish embryos. In a PCR experiment, a primer is used to find and isolate the desired nucleotide sequence of DNA (2). In this experiment two primers were used as follows:
Deoxyribo Nucleic Acid (DNA) is a chromosome found in the nucleus of a cell, which is a double-stranded helix (similar to a twisted ladder). DNA is made up of four bases called adenine (A), thymine (T), guanine (G), and cytosine (C), that is always based in pairs of A with T and G with C. The four bases of A, C, G, and T were discovered by Phoebus Levene in 1929, which linked it to the string of nucleotide units through phosphate-sugar-base (groups). As mention in Ananya Mandal research paper, Levene thought the chain connection with the bases is repeated in a fix order that make up the DNA molecu...
The colonization of each continent by modern human populations remains an important question in our history as a species. Studies of variations in mitochondrial genomes, Y-chromosomes, satellite DNA, and other genetic markers can be used to estimate the time of divergence of one population from another. Recent advancements in technology have advanced our capabilities in genetic analysis. In particular, PCR can be used to amplify, study, and sequence DNA from long-deceased specimens.
What has to happen for a gene to be transcribed? The enzyme RNA polymerase, which makes a new RNA molecule from a DNA template, must attach to the DNA of the gene. It attaches at a spot called the promoter.
Gel electrophoresis is used in a variety of settings, particularly in molecular biology. Besides being used to separate nucleic acids, such as DNA and RNA, gel electrophoresis is also employed to divide proteins (Gel Electrophoresis). According to research, electrophoresis is applied for the following reasons, "To get a DNA fingerprint for forensic pur...
Every cell in every living organism contains DNA, or deoxyribonucleic acid. DNA is wound up around proteins to form chromosomes, and along these chromosomes are sections which code for different traits in the organism, known as genes. Thus the program of genetics is written in the language of DNA (Steitz undated). Chromosomes are comprised of thousands of genes, each having specific sequences of nucleotides which code for specific traits in the organism or functions within each cell. These features could include eye or hair colour of a human, or a specific protein or enzyme which can produce an organism’s inherited traits (Steitz undated).
DNA (deoxyribonucleic acid) is a self-replicating molecule or material present in nearly all living organisms as the main constituent in chromosomes. It encodes the genetic instructions used in the development and functioning of all known living organisms and many viruses. Simply put, DNA contains the instructions needed for an organism to develop, survive and reproduce. The discovery and use of DNA has seen many changes and made great progress over many years. James Watson was a pioneer molecular biologist who is credited, along with Francis Crick and Maurice Wilkins, with discovering the double helix structure of the DNA molecule. The three won the Nobel Prize in Medicine in 1962 for their work (Bagley, 2013). Scientist use the term “double helix” to describe DNA’s winding, two-stranded chemical structure. This shape looks much like a twisted ladder and gives the DNA the power to pass along biological instructions with great precision.
Coughlin, S. S. (2002). Future challenges for research on diagnostic tests: genetic tests and disease prevention. Journal of Epidemiology & Community Health, 56(5), 335-336. doi:10.1136/jech.56.5.335
Amplification reaction was done in a 25.0 µL reaction mixture containing 0.4 µL DNA (from DNA extraction), 5.0 µL of 10X PCR reaction buffer, 14.2 µL of sterelized dH2O, 2.0 µL of magnesium chloride (MgCl2, 25 mM), 1.0 µL nucleotide/dNTP mix (10 Mm), and 0.4 µL of 5 u/µL Taq DNA polymerase for each primer namely respectively. The components and the volume used for the amplification reactions are listed in Table 3.2. For the reaction, PCR reaction was performed in a programmable gradient-enabled thermocycler (Bio-Rad MyCycler™ Thermal Cycler).
The reconstruction of DNA has brought many cures against genetic diseases that before were undetectable. Although it is not a treatme...