DNA fingerprinting

Context: Recently Delhi Police recovered bones from the Mehrauli forest area in connection with the Shraddha Walkar murder investigation. DNA testing conducted on the bones — parts of the jaw, pelvis and lower limb — has now confirmed a positive match with Shraddha’s father.

About DNA fingerprinting:

• “DNA fingerprinting is a procedure that shows the hereditary cosmetics of living things. It is a strategy for finding the distinction between the satellite DNA areas in the genome.”
• DNA profiling, DNA testing, DNA examination, Genetic profile, DNA distinguishing proof, genetic fingerprinting, and genetic investigation are a portion of the mainstream names utilized for DNA fingerprinting. This technique was invented by Alec Jeffreys in 1984.
• Sources of DNA:
  • hair,
  • bone,
  • teeth,
  • saliva,
  • blood, etc.
• Because there is DNA in most cells in the human body, even a minuscule amount of bodily fluid or tissue can yield useful information.
• DNA evidence is used to solve crimes in two ways:
  • If a suspect is known, that person’s DNA sample can be compared to biological evidence found at a crime scene to establish whether the suspect was at the crime scene or whether they committed the crime.
  • If a suspect is not known, biological evidence from the crime scene can be analysed and compared to offender profiles in existing DNA databases to assist in identifying a suspect.

Uses of DNA Fingerprinting:

• Forensic analysis: It can be used in the identification of a (1) person involved in criminal activities, (2) for settling paternity or maternity disputes, and (3) in determining relationships for immigration purposes.
• Pedigree analysis: It can be used for inheritance pattern of genes through generations and for detecting inherited diseases such as Cystic Fibrosis, Haemophilia, Huntington’s Disease, Sickle Cell Anaemia etc.
• Personal Identification: DNA fingerprints can be used as a genetic bar code to identify individuals.
• Anthropological studies: It is useful in determining the origin and migration of human populations and genetic diversities.
• DNA Barcoding: A technique for specifying the organisms’ species using a short sequence of DNA situated in the genome is termed DNA bar-coding. The barcode DNA sequences are too short in respect to the complete genome and hence cheaper.

DNA Fingerprinting in India:

• Pioneering work was done by Lalji Singh at the Centre for Cellular and Molecular Biology (CCMB), Hyderabad

Other centres are :

• Centre for Cellular and Molecular Biology (Hyderabad)
• Centre for DNA Fingerprinting & Diagnostics (Hyderabad)
• Central Forensic Science Laboratory, Kolkata
• National Bureau of Plant Genetic Resource (NBPGR), New Delhi
• National Institute of Plant and Genetic Research (NIPGR), New Delhi

Source: Indian Express

Previous Year Questions

Q.1) Consider the following statements: DNA Barcoding can be a tool to:

1. assess the age of a plant or animal.
2. distinguish among species that look alike.
3. identify undesirable animal or plant materials in processed foods.

Which of the statements given above is/are correct? (2022)

1. 1 only
2. 3 only
3. 1 and 2
4. 2 and 3

Q.2) With reference to the recent developments in science, which one of the following statements is not correct? (2019)

1. Functional chromosomes can be created by joining segments of DNA taken from cells of different species.
2. Pieces of artificial functional DNA can be created in laboratories.
3. A piece of DNA taken out from an animal cell can be made to replicate outside a living cell in a laboratory.
4. Cells taken out from plants and animals can be made to undergo cell division in laboratory petri dishes.