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DNA Fingerprinting: Definition, Method and Application

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What is DNA fingerprinting? DNA fingerprinting is a laboratory technique that is used to determine the identity of a person using a unique pattern in the minisatellites of the genome of an individual. It was first invented in 1984 by Sir Akec Jeffreys after he realized that we can detect variations in human DNA based on these minisatellites. On average, about 99.9% of DNA between two individuals is the same, the remaining 0.1 % makes the person unique. DNA profiling, DNA testing, DNA examination, Genetic profiling, and Genetic fingerprinting are branches of DNA fingerprinting. Following is the complete process of DNA fingerprinting: RFLP (Restriction Fragment Length Polymorphism) The first step of DNA fingerprinting is to extract DNA from the biological fluid of human-like blood, buccal swabs, etc. Then molecular scissors, also called restriction enzymes are used to cut the DNA into thousand pieces of different lengths. These pieces of DNA are now separated using gel electrophoresis...
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History of Fingerprint Science

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Prof. Jan Evangelista Purkinje The history of fingerprint science dates back three 3000 years as it was first used in Chinato to sign legal documents. Then, In 1823 Prof. Jan Evangelista Purkinje published a thesis describing the friction ridge patterns and classifying fingerprints into Nine categories. Sir William Herschel In 1858, An English civil servant Sir William Herschel posted in Bengal, India, started the practice of recording handprints of native Indians to sign the contract. This, greatly prevented the cheating and impersonation among native Indians to sign the contract. But, William Herschel did not publish any of his findings. Dr. Henry Fauld In 1874, Dr. Henry Fauld , a Scottish physician working in a hospital in Tokyo, Japan, published his theory on the potential use of fingerprints for personal identification. In 1880, Dr. Fauld suggested that skin ridge patterns can be proved important for the identification of criminals. He also published his findings in Boo...
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Crime Scene: Definition, Types and Characteristics

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What is a Crime Scene ? A place where the crime is committed or where the maximum physical evidence related to crime is found is known as a crime scene. A crime scene is a starting point of the investigation which provides information about the suspect and the victim. This helps to reconstruct the crime and fast resolution of the case. It is noted that the crime scene is not limited to a single place but may extend to a wider area depending upon the nature of the crime committed. For example, In a murder case where murder is done at one place and the body is disposed on another place. In this case, we have two crime scenes that give information about the crime. Types of Crime Scene Based on evidence found on the crime scene: 1. Primary Crime Scene The crime scene where the actual crime occurred or where more usable pieces of evidence were found is known as the primary crime scene. For example, A murder scene, theft, assault, etc. 2. Secondary Crime Scene The crime scene which is some...
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