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A Dna Bank Is Good For All

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Imagine that a convicted child molester is released from jail and

that he is now traveling around the country looking for work. One day

this criminal returns to his old ways and he attacks a young child whose

dead body is found in a deserted field the following day. The only trace

of evidence at the crime scene is a semen specimen on the boys clothes.

Now this specimen could be useful if the police tracked down, and arrested

the suspect, and then took a blood sample of his that matched the crime

scene specimen. But, since no other clues are found this criminal was

never arrested and for the next couple years he repeated this act many

more times. It is a shame that innocent children had to die because of

this sick man, and most people would agree criminals like this should be

stopped at any cost. Now just think what would have happened had their

been a DNA data bank that contained this man To understand why a DNA

data bank is necessary it is important to know exactly what DNA is.

Firstly, there are cells which makes up all organisms and inside these

cells are chromosomes. Chromosomes, which are made up of DNA, contain all

the hereditary information that an individual has. Now this DNA

(Deoxyribonucleic acid) which makes up these chromosomes simply contains

the blueprints of the organism. It is DNA which determines what, where,

and when to make a certain protein, and it basically is the storage center

for information in almost all creatures. This knowledge of DNA is

important because now it is possible to show the correlation between DNA

and forensic technology.

There are many reasons why DNA is such a useful tool for law

enforcement. One important feature of DNA, relates to the fact that all

individuals have unique DNA, is that each cell in an organism has

identical DNA. Whether it is found in in skin cells, hair cells, semen

cells, or blood cells the DNA found in one cell is identical to the DNA

found in all other cells in the body Another extremely crucial

characteristic of DNA is that everyone has their own unique DNA. Since

humans in general are basically alike in that we all have legs, arms,

hearts brain it is obvious that most DNA is identical. The key though to

identifying individuals through DNA is not through the strands of DNA that

have a known function, rather it is the DNA that has no known function.

Inside these strands of DNA with no known function, called Junk DNA, are

different repetitive DNA patterns which are unique from person to person.

This is why DNA can always, be traced back to one person (with the

exception of identical twins).

There are two tests for analyzing DNA for forensic use, Restriction

Fragment Length Polymorphism (RFLP), and Polymerase Chain Reaction (PCR).

The RFLP test consists of taking a sample of body tissue which contains

DNA. After locating the DNA thousands of different combinations of DNA

repeats called Variable Number of Tandem Repeats (VNTR) are examined.

These VNTR There are a great number of reasons to have a DNA data

bank, but first it is important to accurately describe the requirements

for this DNA data bank. Only convicted criminals would be entered into

the bank. Also, only Junk DNA would be kept as data, DNA that contains

no personal or hereditary information. One advantage to a data bank will

be the quick access to information. Prosecutors are going to be able to

match the DNA collected at a crime scene with DNA that has already been

collected in the bank and this will allow them to apply for a warrant

faster. Take the case of Jean Ann Broderick. In 1991 she was found

murdered and raped in her Minnesota apartment. There were no witnesses or

evidence that led to any one suspect. The only lead at the crime scene

was a semen stain on the victim. Minnesota at this time was one of the

few states that had and used a DNA data bank of convicted criminals, so

the Minnesota authorities checked their sample DNA with the DNA data bank

and found a match that linked the DNA with Martin Perez, a 37 year old

illegal alien. After Perez was identified by the DNA, he was also

identified by witnesses, who saw him at Jean Ann Broderick Another

advantage of having a DNA data bank is that it is much easier to identify

repeat offenders. Most sexual offenders commit a series of crimes, so

the importance of a DNA data bank can obviously be seen. The DNA

specimen left at the crime scene can be used to identify a suspect before

other similar crimes are convicted. A situation like this occurred




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