Question

The probe used initially by Alec Jeffrey during development of DNA fingerprinting was

• A. SAT chromosomes
  
• B. VNTR
  
• C. rDNA
• D. Ribozyme

Answer 1

The correct option is B VNTR


DNA fingerprinting
DNA fingerprinting is a technique that allows the identification of variations which are unique to each organism using a VNTR probe that shows a very high degree of polymorphism.

Ribozyme
Ribozyme is an enzyme whose biochemical nature is RNA.
It is capable of catalysing biochemical reactions.
For example: 23S rRNA is a ribozyme that forms a peptide bond between amino acids during translation.

SAT chromosomes
SAT stands for Satellite chromosome.
SAT chromosomes are chromosomes that have a separate segment present as secondary constriction.
Examples include chromosomes 13, 14, 15 in humans.

VNTR
VNTR (Variable Number of Tandem Repeats) is a satellite DNA that has a very high degree of polymorphism (variations at genetic level).
Alec Jefferey used these short variable tandem repeats VNTR as a probe for DNA fingerprinting.

rDNA
rDNA stands for recombinant DNA that is formed by the insertion of foreign DNA in a vector.

Final answer
(C) VNTR