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DNA profiling
Have you heard "DNA profiling" ?
you may look used in the criminal investigation and the parentage diagnosis by the some media.
It is important data in the criminal investigation all over the world in reality.
In fact, the target of DNA profiling is not only human.
It does to farm animals and products and it is used as a data to judge of the breed.
DNA profiling is researching STR, it stands for "Short trandem repeat".
STR is the area repeating same arrangement with a length of few bases.
there are some such area in human's DNA and it is different from each other.
This is used to judge, the criminal investigation and the parentage diagnosis.
Procedure
First of all, it is necessary the sample.
When you find from the fingerprints, the cells of the skin is used.
If the fingerprints were wiped, there are the cells.
When you find from the hair, the cells of the hair root.
The hair root is the grain, is stuck to the tip of the hair.
Some people are confused that you could get the hair without the cells, you cannot DNA profile.
Saliva don't have the cells.
So, when you find from the saliva, what is checked on?
The answer is the cells come off from skin inside each cheek.
There are the cells to DNA profile.
DNA is against dry, so you can DNA profile from the dry blood and past blood.
On the other hand, it is weak for chemical changing for example by the radiations, by the acids, by the alkalis.
The DNA are increased by PCR methods.
The technology can increase it to check on STR if it was few.
Current method needs DNA about 1 nano gram, it is enough from only one cell.
You can use DNA profiling to chose proper area and to compare the repeating pattern and the number of times.
However, you have to think over this checks on only pattern.
there may be the same pattern, there are the examples in the trials in reality.
So we cannot be too careful.
Nowadays, distinguishing is impossible only by DNA profiling because of a few samples of it.
For this reason, it is used as the refinement of suspects or identifying the body rather than as the testimony.
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