Following the collision of two trains a large number of passengers are killed. A majority of them are beyond recognition. Authorites want to hand over the dead to their relatives. Name a modern scientific method and write the procedure that would help in the identification of kinship. (3 marks)
DNA fingerprinting is the method which will help in the identification of kinship.
Procedure of DNA Fingerpreinting.
The technique that would help establish the identity of the dead is DNA fingerprinting. DNA polymorphism is the basis of DNA fingerprinting. In some specific regions a small stretch of DNA is repeated many times known as repetitive DNA. They do not code for any proteins but they form a large portion of human genome. These sequences show high degree of polymorphsim. Since DNA from every tissue such as blood, hair-follicle, skin, bone, saliva, sperm etc. show the same degree of polymorphsim, they become very useful identification tools in forensic applications.
DNA fingerprinting technique :
(i) Isolation of DNA
(ii) Digestion of DNA by restriction endonucleases.
(iii) Separation of DNA fragments by gel electrophoresis. VNTRs are multiplied by PCR technique if
(iv) Transferring (blotting) of separated DNA fragments of synthetic membranes, such as nitro-
cellulose or nylon.
(v) Hybridisation using labelled VNTR probe.
(vi) Detection of hybridised DNA fragments by auto radiography.
(viii) The autoradiogram gives bands of differing sizes. These bands give a characteristic pattern
for an individual DNA. It differs from individual to individual in a population except in the
case of monozygotic (identical) twins.