The technique popularly known as DNA fingerprinting was first described by Sir Alec Jeffreys in 1985. Which class of polymorphic markers did his original method exploit?

• A Single nucleotide polymorphisms detected by microarray
• B Mitochondrial D-loop sequencing
• C Short tandem repeats amplified by multiplex PCR
• D Minisatellite variable number tandem repeats probed by Southern blotting ✓

Explanation

Jeffreys' original fingerprint used multilocus probes against hypervariable minisatellite (VNTR) regions, visualised by restriction digestion and Southern blotting. Modern profiling replaced this with fluorescent multiplex PCR of short tandem repeats, which is the current standard. The key distractor is option C because STRs are the modern successor, but they were not part of the original 1985 fingerprinting technique described by Jeffreys.

Reference: Butler, Forensic DNA Typing, 2nd ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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