Model Answer
0 min readIntroduction
DNA fingerprinting, also known as DNA profiling, is a laboratory technique used to establish a link between biological evidence and a suspect in a criminal investigation or to establish paternity. Developed by Sir Alec Jeffreys in 1984 at the University of Leicester, it revolutionized forensic science. The technique relies on variations in individuals’ DNA, specifically in repetitive sequences called Short Tandem Repeats (STRs). In India, the use of DNA fingerprinting is governed by legal frameworks, most recently updated by the DNA Technology (Use and Application) Bill, 2019, aiming to expand its application and establish a national DNA database.
What is DNA Fingerprinting?
DNA fingerprinting is a process of identifying individuals based on their unique DNA patterns. It doesn’t analyze the entire genome but focuses on highly variable regions called Short Tandem Repeats (STRs). These STRs are short DNA sequences repeated multiple times, and the number of repeats varies significantly between individuals. The process involves:
- DNA Extraction: Isolating DNA from cells (blood, saliva, hair roots, etc.).
- PCR Amplification: Using Polymerase Chain Reaction (PCR) to amplify specific STR regions, creating millions of copies.
- Capillary Electrophoresis: Separating the amplified DNA fragments based on size.
- Analysis & Comparison: Generating a DNA profile (a series of peaks representing STR lengths) and comparing it to other profiles.
The resulting DNA profile is highly specific to an individual, making it a powerful tool for identification.
Precautions While Collecting Samples from Living Human Beings
Maintaining the integrity of DNA evidence is paramount. Improper collection or handling can lead to contamination, degradation, or misinterpretation of results. The following precautions are crucial:
- Chain of Custody: Maintaining a documented and unbroken chain of custody from collection to analysis.
- Proper Collection Materials: Using sterile swabs, tubes, and containers specifically designed for DNA collection.
- Avoiding Contamination: Wearing gloves, masks, and protective clothing to prevent contamination from the collector’s DNA.
- Proper Labeling: Clearly labeling each sample with the individual’s name, date, time, and location of collection.
- Storage Conditions: Storing samples in a cool, dry place, away from direct sunlight and extreme temperatures.
- Documentation: Detailed documentation of the collection process, including photographs and witness signatures.
- Informed Consent: Obtaining informed consent from the individual before collecting the sample, explaining the purpose of the test and potential implications.
- Sample Type: Choosing the appropriate sample type. Buccal swabs (cheek swabs) are commonly used for living individuals as they are non-invasive.
Specific considerations for different sample types: Blood samples require proper anticoagulants. Saliva samples should be collected without food or drink contamination. Hair samples should include the root.
The DNA Bill (DNA Technology (Use and Application) Bill, 2019)
The DNA Technology (Use and Application) Bill, 2019, passed by the Lok Sabha in March 2023, aims to establish a national DNA database to solve crimes more effectively. Key provisions include:
- National DNA Index (NDI): A central repository of DNA profiles.
- State DNA Index (SDI): A database maintained by individual states.
- DNA Data Bank: A secure facility for storing DNA profiles and related information.
- DNA Profiles Covered: The Bill allows for the collection of DNA profiles from individuals convicted of specified offenses, arrested for offenses carrying a punishment of seven years or more, missing persons, unidentified deceased persons, and their relatives.
- Data Security & Privacy: The Bill includes provisions for data security and privacy, with penalties for misuse of DNA data.
- DNA Regulatory Board: Establishment of a DNA Regulatory Board to oversee the functioning of the DNA data bank and ensure adherence to ethical guidelines.
Concerns & Criticisms: The Bill has faced criticism regarding potential privacy violations, the broad scope of DNA collection, and the possibility of misuse of the database. Concerns have been raised about the potential for mass surveillance and discrimination.
| Feature | DNA Bill 2019 |
|---|---|
| Purpose | Establish a national DNA database for criminal investigations and identification. |
| Data Sources | Convicts, arrestees (for serious offenses), missing persons, unidentified deceased, their relatives. |
| Data Storage | National DNA Index, State DNA Index, DNA Data Bank. |
| Privacy Safeguards | Data security provisions, penalties for misuse, DNA Regulatory Board. |
Conclusion
DNA fingerprinting remains a cornerstone of modern forensic science, offering a powerful tool for identification and justice. The DNA Bill, while aiming to enhance crime investigation, necessitates careful implementation to safeguard individual privacy and prevent potential misuse. Balancing the benefits of DNA technology with ethical considerations and robust data protection measures is crucial for its responsible application in the Indian context. Continuous monitoring and refinement of the legal framework will be essential to address emerging challenges and ensure public trust.
Answer Length
This is a comprehensive model answer for learning purposes and may exceed the word limit. In the exam, always adhere to the prescribed word count.