Recombinant DNA Technology | Zoology Optional Notes for UPSC PDF Download

What is recombinant DNA technology? A definition

• Recombinant DNA technology is a means to generate recombinant DNA. This process involves the manipulation and isolation of specific DNA segments from different species. DNA segments are joined by attaching them to the DNA of a virus or bacterial plasmid and then inserted into a host cell.
• Plasmids, artificial chromosomes, or bacteriophages are commonly used as vectors in molecular cloning to drive the replication of recombinant DNA sequences within host organisms.
• There are several pros and cons of recombinant DNA, with ethical and religious concerns being the main disadvantages. However, genetic engineering offers great opportunities in the research and production of innovative medical or therapeutic products.

History of recombinant DNA technology

The structure of DNA was first determined in 1953, but it wasn't until the early 1970s that the first recombinant DNA molecules were produced using restriction enzymes. Paul Berg succeeded in proving the possibility of splicing and recombining genetic material in 1971. Stanley Cohen and Herbert Boyer were able to cut and fuse specifically located DNA strands, leading to the approval of a patent for recombinant antibody technology in 1980.

Examples of recombinant DNA technology

Examples of recombinant DNA technology in the health sector

The first commercial healthcare product derived from rDNA was human insulin. Today, it is successfully used to produce new antibodies, vaccines (e.g., for Hepatitis B), and different protein production systems, such as insulin and human growth hormone.

Here are 5 examples of rDNA technology in the health sector:

• Human Growth Hormone (hGH): rDNA technology produces hGH for treating growth disorders in children.
• Erythropoietin (EPO): Engineered EPO helps manage anemia in patients with kidney failure and cancer.
• Tissue Plasminogen Activator (tPA): rDNA-derived tPA is used to dissolve blood clots in stroke patients.
• Herceptin (Trastuzumab): This rDNA-made antibody targets HER2-positive breast cancer cells.
• Factor VIII: Recombinant Factor VIII treats patients with hemophilia A, promoting blood clotting.

rDNA and agriculture - examples

Recombinant DNA technology is used to genetically modify plants to improve adaptability, resistance to harmful agents, and enhance product yield.

Examples of rDNA technology in agriculture include:

• Bt Crops: Genetically modified crops that express a bacterial gene from Bacillus thuringiensis, providing built-in insect resistance.
• Golden Rice: Genetically engineered rice that produces beta-carotene to combat Vitamin A deficiency.
• Roundup Ready Crops: Crops designed to be resistant to the herbicide glyphosate, allowing effective weed control.

Recombinant DNA technology: examples in the food industry

Recombinant DNA technology enables the manufacturing of novel enzymes to prolong shelf life and kill foodborne pathogens.

Here are 3 examples of recombinant DNA technology in the food industry:

• Chymosin (Rennet): Genetically modified microorganisms are used to produce chymosin for cheese production.
• High-Fructose Corn Syrup (HFCS) Production: rDNA technology enhances the enzymatic conversion of corn starch into glucose and fructose.
• Bioengineered Food Additives: rDNA technology is employed to produce various food additives and enzymes used in food processing.

Recombinant Production

Recombinant DNA technology involves the isolation and manipulation of genetic material to improve certain characteristics. It differs from genetic recombination, which is a natural biological process.

Methods in recombinant Technology

There are three different methods of producing recombinant DNA: transformation, non-bacterial transformation, and phage introduction. These methods involve the insertion of DNA segments into host cells, either with or without the use of bacteria.

Steps in Recombinant DNA Production

The production of recombinant DNA involves the isolation of genetic material, cutting of DNA at specific locations, joining of DNA fragments, insertion into host cells, and selection and screening of transformed cells.

What is needed in recombinant technology?

In recombinant DNA technology, DNA sequences from various sources can be used. Enzymes, gene cloning vectors, polymerase chain reaction (PCR), and host organisms are important tools in this field.

What about safety?

Recombinant DNA molecules and recombinant proteins are generally not regarded as dangerous. However, concerns exist regarding the safety of organisms expressing recombinant DNA, particularly in terms of environmental impact and potential health effects.

The prospects in recombinant DNA technology

Recombinant DNA technology plays a vital role in improving health conditions and addressing plant disorders. The global market for recombinant DNA technology is expected to reach USD 223 billion by 2028, with a projected annual growth rate of 7.7%.