Gene+Extraction

=Gene Extraction=

How do we reap the DNA samples we need in order to receive the information on the human (or that of an animal's) genome?

//DNA extraction is important because it allows for use to gain the information to see if a person or animal has a genetic disease, to study its forensic evidence, or even to discover if someone has a gene involved in cancer. DNA extraction allows for us to __purify__ the DNA before we study it!//

There are many ways to do this, some more sophisticated than others...

Ask any middle schooler, and they'll tell you about that time their teacher made them swab the inside of their mouth with a toothpick. In fact, ask any high schooler, and they'll most probably have had to do the same. Or, as in Mr. Plamann's SL Bio class, they'll talk to you about that time they spit two mL of spit into a test tube.


 * **Quick Guide for DNA Precipitation and Extraction**

DNA Precipitation: this is the procedure in which a DNA sample, at this point still an extract containing billions of DNA strands, proteins, and other substances that make it hard to analyze the DNA bands, is purified in order to then be able to proceed to extract the individual strands.

For a diagram of DNA extraction, before the purifying, please see below. It is important to notice that we use alcohol when extracting DNA, because it is less dense than water, allowing the DNA to float!

So, for a more detailed procudre go to this link...[|Procedures] It also shows how using alcohol is very common in preparation for an DNA extraction. Also, a centrifuge is used to spin the samples in order to unbind, help wash and purify the DNA.



Just as in the above diagram the seaweed is "purified" into its various components, and thus only what we really "want" is used for further processing, we take the DNA strand apart and extract what it is we really want to further analyze.

Buy your own [|purifying alcohol]o, in case you're contemplating trying this in an experiment at home!

DNA Extraction: One separates the DNA strands in order to further analyse its base sequences.


 * This quick and user freindly slide show is a great way to see the simpliest form of DNA extraction!
 * the steps include:collecting samples, bursting open the cells to release DNA, seperating the DNA from proteins and other substances and finally isolated the concentrated DNA!
 * [|DNA Extraction Guide]

Another way, for instance when wishing to extract of either **vegetables or animals** (since it'd be slightly difficult to a) find a cow and b) swab its cheek), here's a quick do-it-at-home experiment! The second link is one with peas which goes into a bit more detail on the materials used to extract DNA at home!


 * [|DNA Extraction II: vegetables and animals]
 * [|DNA Extraction II: peas]

Buy your own [|extraction kit] to go through the procedure yourself, shown here:

here's an interesting article the New York Times posted on Feb. 5th, 2007 about [|US Scientists' DNA Sampling:]

then of course there's the **DNA extraction from blood samples**. > >> > >> [|Ambion] > >> [|Panomics]
 * To see how the experts do it, take a look at the materials and a so called simple procedure for extracting DNA from blood!
 * [|DNA Exrtaction I: blood]nowadays there are numerous companies that offer their services in extracting DNA or RNA.

This is often used in DNA Profiling in crime investigations, as blood samples hours or days old will still hold the same genetic material as blood taken right from the arm of a suspect. The DNA bands can then be compared using, for example, gel electrophoresis. -> find out about the [|story behind it] here!

However, crime scenes are not the only place where DNA sampling is used! A further way DNA is used after extraction is in the process of DNA screening, through which we can identify genetic diseases by matching DNA from parents, children and relatives. This DNA extraction can help us differientiate between mitochondrial DNA (DNA inherited through the mother) and chromosomal DNA, which is the 'typical' DNA we talk of in our chromosomes.

SO.......How does DNA extraction and it's uses play a role in your life?