Q. In genetic fingerprinting, the ‘probe’ refers
to ––––––
(a) a radioactively labelled single stranded DNA molecule.
(b) a radioactively labelled single stranded RNA molecule.
(c) a radioactively labelled double stranded RNA molecule.
(d) a radioactively labelled double stranded DNA molecule
Answer (a) : For DNA fingerprinting special single stranded DNA-probes are made in the laboratory. DNA-probes contain repeated sequences of bases complementary to those on VNTRs. These probes are made radioactive by labelling with radioactive isotopes. This step helps in detecting DNA fingerprints or variable number of tandem repeats (VNTRs).
