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Why was recombinant insulin an important milestone in biotechnology?

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A step-by-step diagram shows donor DNA and vector DNA cut with restriction enzymes to create overhangs, mixed and sealed with ligase to form recombinant DNA, which is introduced into bacterial cells. The recombinant DNA replicates as the cells divide, producing clones. — biotechnology Steps involved in the engineering of a recombinant DNA molecule.

The development of recombinant insulin was a landmark achievement in biotechnology because it marked the first time a clinically significant, synthetic human protein was successfully manufactured as a pharmaceutical product.1

Approved for use in 1982, this milestone was made possible by recombinant DNA technology. Scientists synthesized the DNA sequence responsible for human insulin production and incorporated it into laboratory strains of Escherichia coli bacteria. This allowed for the large-scale production of insulin that is identical to the natural form found in the human body.12

Prior to this innovation, patients with diabetes relied on insulin extracted from the pancreases of cows or pigs. While these animal-derived products were effective for decades, the ability to synthesize human insulin through genetic engineering provided a reliable, scalable, and chemically identical alternative. This breakthrough paved the way for the production of other essential human proteins, such as growth hormone, and demonstrated the immense potential of applying genetic engineering to medical science.132