Dna Marker Research Paper

1. If each individual has such a small amount of DNA, how do the bands on the gel contain enough DNA to be visible?

There are three specific steps required to isolate DNA from its cellular contents. The steps used to remove and expose DNA from its cell are: breaking down the food type you are using by crushing it, for example a banana or strawberries, exposing the substance to a sodium chloride (NaCl) solution, subjecting the product to detergent solution (dH2O), filtering the solution and lastly, the addition of ethanol. When beginning with a solid substance, such as a banana, crushing the substance allows for

Each human being has something called DNA. DNA is described as genetics and an extremely long macromolecule that is the main component of chromosomes and is the material that transfers genetic characteristics in all life forms. DNA constructs of two nucleotide strands coiled around each other in a ladder like arrangement with the sidepieces composed of alternating phosphate and deoxyribose units and the rungs composed of the purine and pyrimidine bases adenine, guanine, cytosine, and thymine. Each chromosome consist of one continuous thread-like molecule of DNA coiled tightly around proteins and contains a portion of the 6,400,000,000 basepairs that make up your DNA.

After the incubation, we removed the tubes from the heating blocks. We then got the package of 1.2% agarose FlashGel. The gel contained a chemical which allows us to see the DNA fragments under the ultra violet light. We marked where each DNA fragment would go on the gel and began to put them in the gel wells. We carefully put 5 micrometers of the crime scene samples into the wells.

Indeed DNA profiling has rapidly transform the field of forensics. DNA profiling is the scientific analysis of evidence for crime scene investigation and other legal proceedings. DNA profiling is mostly used by forensic scientists and crime lab technicians. To identify criminals and victims using trace evidence like hair or skin samples. To produce a DNA profile, scientists compare sequences in the genome that vary from person to person. The typical steps in DNA profiling are DNA samples are isolated from the crime scene, suspect, victims, or other evidence. The next selected sequences from each DNA sample are amplified (copied many times) to produce a large sample of DNA fragments. Finally the amplified DNA regions are compared using a gel. All together, these steps provide data about which samples are from the same individual and which sample is unique.

The idea behind Gel Electrophoresis is that we inject a slab of gel with the DNA we found at the crime scene. We then inject the same gel, next to the crime scene DNA, with suspect 1’s DNA and suspect 2’s DNA. We then send an electric current through the gel and wait for the results. The smaller molecules in the DNA will travel farther than the bigger molecules because the bigger ones will have difficulty making its way through the microscopic beads in the gel. After the separate bands appear in the gel, we stain it with a special chemical called Ethidium Bromide to give it a color under the blue

Another machine that is used is the Molecular Dynamics Fluorimager FSI. This device is a quantitative gel and blot system in order for scientists to read. This labels the DNA and proteins on micro plates. A laser scans the DNA a then provides an image for studying the DNA (Harkey, 2002).

DNA Fingerprinting, also known as DNA Profiling, is a method used to identify a person using DNA patterns that are specific to him/her. 99.9% of DNA is identical in every human being, but .01% is enough to distinguish between people. It is most commonly used in criminal cases to link a criminal to his/her crime scene, but is also used for paternity/maternity tests, and immigration records. Usually a skin, hair, or body fluid sample is collected from a crime scene or criminal or test candidate, then DNA is extracted and cut using enzymes that recognize patterns in DNA and run through a gel by an electric current in a process called electrophoresis (Annely).

Let the agarose powder sit in the buffer for a few minutes. The beaker is covered with plastic wrap an placed in the microwave. Microwave the solution slowly with boiling it. As soon as the solution starts to boil, take it out and carefully mix it with the hot gloves on and continue to heat the solution until it is completely clear. Once the solution is cooled, add 3µL of ethidium bromide stock to the solution and mix it by swirling it. The gel is poured into the prepared mould that is taped on the ends and eliminate any bubbles. Place the comb on the negatively (-) charged side. After the gel solidifies, remove the comb and tape and place the gel into the chamber. Gently pour TAE buffer over the gel as the gel should be completely covered by 2-3 mm of buffer. If air bubbles form, gently displace them with a disposable micropipette tip. Droplets of prepared loading buffer are placed on a piece of parafilm paper. The ladder will consists of only the buffer because it will work as a measuring device to compare the DNA samples. 10 µL from each of the DNA samples will be mixed with the loading buffer using the micropipette tip. The positive control will be consist of 10 µL of water and the droplet of loading buffer. The samples including the ladder and positive control are added to a separate well in the gel. Once all of the samples are loaded into their own

To determine which dye had the most net charge and its macromolecule size. Introduction: Gel Electrophoresis is a technique used in Molecular Biology to separate macromolecules based on their size and their charge (negative/positive). For this experiment DNA was analysed, DNA has a negative charge. There are two unknown mixes of dyes.

A comb was then inserted to create wells for the chemicals (or in real life DNA) to be placed. After the gel has become solid we then removed the comb as well as the tape and placed the agarose into an electrolysis chamber with the plastic facing perpendicular to the leads. To this chamber was added ~250ml of trisborate EDTA which was used as a buffer as well as a conductor so that the electricity can flow through. After this we used a 10ml micro pipette to insert the following; bromophenol blue, crystal violet, orange g, malachite green, xylene cyanol, and a dye mixture (as a baseline) into lanes 1-6 in that order (malachite green in 1 dye in 6). Once these chemicals locations were recorded we were ready to turn it on.

Nucleic acid molecules which are to be analyzed are set upon a viscous medium, thegel, where an electric field induces the nucleic acids to migrate toward the anode, due to the net negative charge of the sugar-phosphate backbone of the nucleic acid chain. The separation of these fragments is accomplished by exploiting the mobilities with which different sized molecules are able to pass through the gel. Longer molecules migrate more slowly because they experience more resistance within the gel. The DNA fragments of different lengths are visualized using a fluorescent dye specific for DNA, such asethidium bromide. The gel shows bands corresponding to different nucleic acid molecules populations with different molecular weight. Fragment size

Let the test tube sit undisturbed for 2 - 5 minutes. You should begin to see air bubbles form at the boundary line between the ethanol and the filtered fruit solution. Bubbles will form near the top, and you will eventually see the DNA float to the top of the ethanol. Gently insert the stir stick into the test tube. Slowly raise and lower the tip several times to spool and collect the DNA. If there is an insufficient amount of DNA available, it may not float to the top of the solution in a form that can be easily spooled or removed from the tube. However, the DNA will still be visible as white/clear clusters by gently stirring the solution and pushing the clusters around the top. Post-Lab Questions What is the texture and consistency of the DNA DNA is viscous and greasy. Why did we use a salt in the extraction solution High salt makes DNA less soluble in water. In order to dissolve, the water needs to interact with the DNA. Since DNA is quite large, it needs to interact with lots of water for this purpose. When you add salt, the water preferentially interacts with the salt (its small, and can move around in solution easier than the DNA can). This makes it so there is less water available to interact with the DNA and it becomes less soluble. Is the DNA soluble in the aqueous solution or alcohol DNA is less soluble in an alcohol such as isopropanol than it is in water. This is because alcohols are non-polar, whereas water is polar. The polar

The polymerase chain reaction or PCR for short can be used to create many copies of DNA. This allows the DNA to then be visualized using a dye like ethidium bromide after gel electrophoresis. The process has been refined over the years, however the basic steps are similar.

The process of DNA fingerprinting in humans involves the replication and arrangement of extracted DNA, to create a pattern/fingerprint that is viable for comparison. This process involves the application of DNA extraction, digestion by restriction enzymes, Polymerase Chain Reaction (PCR) and gel electrophoresis. This results in a DNA profile with bands of varying widths that can be used for the comparison of genetic information. DNA extraction occurs in three stages. Firstly, a