Recombinant DNA technology involved the following steps (i) Isolation of DNA (ii) Fragmentation of DNA by restriction endonucleases (iii) Isolation of a desired DNA fragment (iv) Amplification of the gene of interest (v) Ligation of the DNA fragment into a vector (vi) Insertion of recombinant DNA into the host (vii) Culturing the host cells on a suitable medium at a large scale (viii) Extraction of the desired gene product (ix) Downstream processing of the products as finished product, ready for marketing