Recombinant DNA Technology Theory Part

The Recombinant DNA (rDNA) Technology refers to the process of joining foreign DNA segments or DNA segments of interest from different sources and introduced them into a host organism for example a bacterial host. This technology enables the construction of new combination of genes or genetic material to be artificially constructed in the laboratory conditions. These rDNA molecules are introduced into the host cells where they can multiply which is to create, replicate and investigate the recombinant DNA molecules.

The best and first example of recombinant DNA technology is Human Insulin produced by bacteria, which was first approved by the FDA in 1982.

A typical Recombinant DNA experiment involves following main steps.

1) Isolation of DNA segments of interest usually gene sequences. (Sequences which are to be manipulated or used and needs to be cloned).

These selected DNA segments are called as Inserts.

2) A specific Vector is selected which acts as a CARRIER DNA molecule, which is used to insert the DNA segments (Inserts) by the process of restriction enzyme digestion and ligation. After inserting the DNA molecule into a vector,

Recombinant DNA = Vector + Insert.

3) Then these ligated recombinant DNA molecules are transformed into a selected host cell by the process for example Transformation.

4) After an appropriate amount of time and laboratory conditions, these transformed cells will produce the colonies which may contain the clones (rDNA = Vector+Insert).

5) Selection of those host cells which carry the rDNA are performed by the process called PCR (Polymerase Chain Reaction) and these clones are used for the library creation or further experiments.

Each cell in the clone may contain multiple copies of the Insert.

Image result for recombinant dna technology gif

(The above information is just the overview and main steps involved).

Practical steps and detailed information will be posted soon.

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