Abstract

Touch DNA viz. trace DNA is a perfect example of Locard’s exchange principle, formulating the basis of forensic science. It basically states that any contact between two objects exchanges a trace amount of matter. Touch DNA is attained from the shed skin cells whenever a person comes in contact or touches any object. This kind of DNA can be found in every sample of fingerprint but its extraction is a cumbersome task in consideration of its trace amount. There is diversity in methods of its extraction but the main problem arises when task is to preserve fingerprint and extract DNA as well. Scientifically, the evidentiary value of fingerprints is 100% and that of DNA is 99.9%. It becomes crucial to preserve both of them to strengthen our case. In this era of vicious and cunning criminals where evidences are obscured. The extraction of touch DNA is practical but not practiced. This study aims at comparing various methods and finding best one out. The most appropriate method should be able to analyze the smallest possible amount of DNA in an economic way and of course leaving the fingerprint indifferent

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