How did recombinant DNA technology make it possible to study and clone genes?

Recombinant DNA technology enables the isolation and cloning of specific genes by treating complex DNA samples as manageable fragments that can be manipulated and amplified.12

The process relies on several key mechanisms:

• Molecular Scissors: Restriction enzymes act as precise tools that cleave DNA at specific target sequences. Many of these enzymes create "staggered cuts," leaving single-stranded overhangs that allow donor DNA fragments to pair with complementary ends on a vector molecule.32
• Vector Insertion: Once the donor DNA and a vector (such as a plasmid or viral genome) are cut with the same enzyme, they are joined using DNA ligase, which seals the sugar-phosphate backbone to create a stable, recombinant molecule.3
• Amplification: These recombinant molecules are introduced into host cells, typically bacteria, through transformation. As the host cells replicate, the recombinant DNA is copied along with the host's own genetic material. When these cells are grown in a DNA library, researchers can isolate and study individual gene clones.3

This technology allows scientists to determine nucleotide sequences, study gene transcripts, and modify specific sequences for further research.1