Question

(a)The steps in DNA finger printing are given. Complete the flow chart (A & B).
(b) Mention the applications of DNA fingerprinting.

Answer 1

The steps in the DNA fingerprinting are:

• Isolation of the DNA
  
• The DNA is fragmented using the restriction enzyme
  
• Separation of the DNA fragments by electrophoresis
  
• Transferring of the DNA to synthetic membrane
  
• Addition of the complementary probes and hybridization
  
• Detection of the hybrid DNA fragments by autoradiography
  

Application of DNA fingerprinting technique:

• DNA polymorphism can be studied. The position and the number of VNTRs are revealed during DNA fingerprinting.
  
• This technique can be useful in the identification of suspect since it is very remote possibility to have two individuals same repeats of satellite DNA throughout the genome except they share a biological relationship.
• Restriction enzymes of genome produce the restriction fragments length polymorphisms, or RFLPs depending on the location of restriction sites which are then sorted by gel electrophoresis followed by southern blotting.
  
• The blots of the suspect and of the sample from the crime scene are compared for sequence homology using radioactive probes.
  
• This can also be used for paternity testing in the case of lost child.
• This method is used in various fields of forensics.