Question

In DNA fingerprinting technique, .......... probe is used for hybridization of DNA fragments.

• A. Double stranded RNA
• B. Double stranded non-radioactive DNA
• C. Single stranded radioactive DNA
• D. Single stranded radioactive RNA

Answer 1

The correct option is C Single stranded radioactive DNA

DNA fingerprinting uses single-stranded radioactive probes which are washed over the nylon surface to allow their joining to any DNA fragments of the same composition thereby matching different DNA samples. Double-stranded probes would not hybridize with DNA fragments present on the membrane and non-radioactive probes can not be detected by autoradiography. Autoradiography helps to localize these radioactively labelled molecules by applying photosensitive emulsion on the surface of the prepared slides.

So, the correct answer is 'Single-stranded radioactive DNA'.