Which technique is most commonly used in DNA fingerprinting for forensic investigations?

• A. Polymerase Chain Reaction (PCR)
• B. Sanger Sequencing
• C. Gel Filtration Chromatography
• D. Restriction Fragment Length Polymorphism (RFLP) analysis

Answer: (D)

Verified step by step guidance

1. Understand the concept of DNA fingerprinting: DNA fingerprinting is a technique used to identify individuals based on their unique DNA patterns. It is commonly applied in forensic investigations to match biological samples to individuals.
2. Learn about Restriction Fragment Length Polymorphism (RFLP): RFLP analysis involves cutting DNA into fragments using restriction enzymes. These enzymes recognize specific sequences in the DNA and cleave it at those sites, producing fragments of varying lengths.
3. Explore the process of RFLP analysis: After the DNA is fragmented, the pieces are separated using gel electrophoresis. This technique sorts the fragments based on their size, creating a distinct pattern of bands for each individual.
4. Compare RFLP to other techniques: While Polymerase Chain Reaction (PCR) amplifies DNA and Sanger Sequencing determines the nucleotide sequence, RFLP is specifically used to analyze variations in DNA fragment lengths, making it ideal for forensic DNA fingerprinting.
5. Understand why RFLP is the correct answer: RFLP analysis is most commonly used in forensic investigations because it provides a reliable and reproducible method for comparing DNA samples and identifying individuals based on their unique genetic profiles.