DNA Fingerprinting

Hello friends, Many of people see different different types of serial regarding a crime. Like Crime Petrol CID, Crime story etc. Or you also see many of crime movies. In that many have question that how the criminal was identified on the basis of one small hair or one small blood sample. So friends that is what today we are going to discuss. Which is DNA fingerprinting I.e criminal finding technique DNA fingerprinting. It is playing huge role in many places. So let see what is actually DNA fingerprinting or DNA profiling.

Who invented DNA fingerprinting

In 1984, Geneticist Alec Jeffreys developed a DNA fingerprinting technique.Using VNTRs i.e. Variable Number of Tandem repeats as a genetic marker. VNTR is place where short nucleotides are arranged in tandem repeat. The idea of this technique is based on length of DNA fragments containing the repetitive sequence. Which is generally called as RFLP i.e. Restriction Fragment Length Polymorphism.

What is DNA fingerprinting

It is a generally a forencic technique as it is used for crime solving. We know that every living thing on planet this may plants or animals are made of cell. That is we all have DNA which is unique. This uniqueness is your identifier which we call as DNA fingerprint. And the technique of finding it is called as DNA fingerprinting or DNA profiling

It was developed to identify by using a simple of blood, semen or from any small body parts. And the most interesting part of this is that about 99% DNA sequence is same in all individuals only 1% difference we found in all the individuals except monozygotic or identical twins. In general about 20 to 100 base pair of DNA sequence shows difference which we call as VNTRs. The length of region of VNTR is different in each individual.

Steps of criminal finding technique DNA Fingerprinting

While processing DNA fingerprinting there has several steps to carried out DNA fingerprinting which is carried out in many forensic and research labs

Step 1 : DNA isolation

First step of this technique is that isolating a DNA from a material that is from blood, semen, hair root or any other small tissue part of body.

Step 2 : DNA amplification

Then after that for obtain more copies of DNA from a single DNA or for amplification of DNA PCR Technique is used.

Step 3 : Fragmentation of DNA

Now for getting different pieces of DNA here all uses a enzyme called as restriction enzyme or restriction endonuclease. Which helps to cut a DNA at specific location. And this phenomenon is called as restriction fragment length polymerization i.e. RFLP.

Criminal finding technique DNA Fingerprinting
Process of DNA fingerprinting

Step 4 : Electrophoresis

In this step fragments of DNA sample are loded in agrose gel electrophoresis. During the electrophoretic run, the negatively charged DNA fragments are displace in the direction of positive pole with respect to there size or we can say length of DNA fragments. As a result we can see formation of bonds.

Step 5 : Southern blotting

Now here we use nitrocellulose paper. Bonds formed in electrophoresis process are blotted on naylon membrane or nitrocellulose paper. Generally In that the single standed DNA fragments is embedded on naylon membrane or nitrocellulose paper.

Step 6 : Hybridization

In this step we here a radioactive DNA of every suspects. After that it flood the single stranded DNA which obtained in last step. And as single standed DNA has natural ability to form a double stranded structure with its suspect DNA. Therefore a double standed structure of DNA is situates in naylon membrane. And remaining samples of DNA are remove back by awshing it.

Step 7 :Photography

After completing these all processes photography is required for documantaion. For this radio active DNA film is kept in contact with X-rays. Which gives us a photographic image.

So it is all about process of DNA fingerprint technique.

Application of DNA fingerprinting

  • It is used for investigation of any crime with help of any small blood, semen, hair root or body tissue sample
  • Also it helps to prove inheritance or solving problems regarding legacy or ownership of a property or insurance claim.
  • It also plays important role in study of phylogeny and genomics
  • For detecting historical vestige
  • It is also used in agricultural study.

So it is all about DNA fingerprinting, what is in actual, its process and steps. So by seeing all this things I conclude here that it is technique where we can say it’s WoW .

Thank You…!

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