Genes of interest can be selected from a genomic library by using :
- Restriction enzymes
- Gene targets
- Cloning vectors
- DNA probes
Answer
(4) DNA probes
Solution
A genomic library contains many clones carrying different DNA fragments of an organism.
⇒ To pick out the clone carrying the gene of interest, a labelled (radioactive or fluorescent) single-stranded DNA probe complementary to that gene is used.
⇒ The probe hybridises only with the complementary sequence, so the colony carrying the gene is identified (colony hybridisation).
∵ Restriction enzymes cut DNA and cloning vectors carry DNA, they cannot identify a particular gene.
∴ Genes of interest are selected from a genomic library using DNA probes.
Answer: (4)