In the development of new genetic combinations useful to research, medicine, agriculture, and industry, the term ‘recombinant DNA technology’ refers to the combining of DNA molecules from two different species that are then introduced into a host organism. One of the most common forms of recombinant DNA (rDNA) is the one that has been formed by combining at least two DNA strands.
When genetic material from various origins is brought together in the laboratory by genetic recombination procedures (such as molecular cloning), they generate DNA molecules that would not normally be found in the genome. Using E. coli restriction enzymes, Herbert Boyer and Stanley Cohen first created a live creature capable of harbouring recombinant DNA in 1973.
Applications of Recombinant DNA Technology
As genetic engineering advances, it is now possible to transfer genes between animals that are not related. We’ve broken down the barriers to genetic exchange between species and even among different taxa. With the application of recombinant DNA technology, the desired genes can be transferred from lower species to higher organisms.
Plants that have been genetically altered so that foreign genes are present are known as transgenic plants. An improvement in quality and disease resistance can be accomplished with this recombinant DNA technology that is used for plant breeding purposes and to improve the quality of crops. One such example is bollworm-resistant BT cotton.
In legumes, the nitrogen-fixing bacteria Rhizobium is found within root nodules, which are a characteristic feature of legumes. In the root nodules, this bacteria transforms free air nitrogen into nitrates. Through the use of genetic engineering, it is now possible to transfer the bacterial genes which are in charge of the nitrogen fixation to cereal crops such as wheat, rice, maize, barley, and so on.
Crop plants’ photosynthetic efficiency can be increased by the development of C4 plants, which can boost yields. Protoplasm fusion or recombinant DNA technology can be used to convert C3 plants into C4 plants, increasing their photosynthetic rate. C4 plants are capable of producing more biomass than C3 plants. Sorghum, sugarcane, and maize are among the most common C4 crops grown in tropical and subtropical regions. The medicinal applications of biotechnology include the creation of antibiotics, hormones, vaccines, and interferon through genetic engineering.
Production of Antibiotics
For the mass manufacture of penicillin and streptomycin, penicillium and streptomyces fungi are utilised. These strains of fungi have been genetically optimised to maximise the number of antibiotics they produce.
The hormone insulin, which diabetics rely on, is often derived from the pancreas of cows or pigs. The structure of this insulin differs somewhat from that of human insulin. As a result, roughly 5% of patients experience allergic responses. The human gene for insulin manufacturing has been inserted into bacterial DNA, and these genetically altered bacteria are utilised to produce insulin on a huge scale. Anti-allergy effects are absent in this insulin. The transfer of antigen-coding genes to disease-causing bacteria is presently the method used to create vaccines. Antibodies against the same bacterium or virus offer protection.
Cells infected with viruses create the protein interferon, which is a virus-induced cytokine. The first line of defence against viruses that cause serious illnesses, including breast cancer and lymph nodes malignancy, is interferon – an antiviral agent. Human blood cells are the only source of natural interferon, which is produced in extremely low quantities. As a result, it is quite pricey. Recombinant DNA technology has made it possible to generate interferon at a significantly lower cost.
Using recombinant DNA technology, some valuable enzymes can be generated. Microorganisms have been genetically modified to create the enzyme urokinase, which dissolves blood clots. When it comes to inherited disorders such as haemophilia, phenylketonuria, and alkaptonuria, scientists hope that genetic engineering will allow them to replace defective genes with healthy ones. This innovative treatment method is termed gene therapy. Recombinant technology is presently the most accurate method for resolving parental disputes than blood tests.
Development of Recombinant Medicinal Products
Technology that uses recombinant DNA has made it easier for doctors to diagnose sickness. In most cases, single-stranded DNA segments are constructed into probes and then linked to a radioactive or fluorescent marker. Infectious agents, such as food poisoning Salmonella, pus-forming Staphylococcus, hepatitis virus, HIV, etc., can be identified with these probes. A parent’s genotype and the likelihood of having a child with a genetic disorder can be predicted through DNA testing of prospective genetic disorder carrier parents.
Recombinant DNA technology can be used in industries to produce commercially important chemical compounds, improve existing fermentation processes, and produce proteins from wastes, among other things. Developing more efficient microorganism strains is one way to attain this goal. Microorganisms that have undergone extensive research and development can even be employed to clean up pollution. Many useful applications of biotechnology and recombinant DNA technologies exist in crop development as well as medicine and industry.
Limitations of Recombinant DNA Technology
Clones of the recombinant organisms are vulnerable in the same ways as any other population of clones. Disease or pests can easily decimate an entire community. Also, people’s genetic information may be taken and utilised without their permission. Many individuals are concerned about the safety of recombinant DNA technology in food and pharmaceutical modification.
As a part of the application of biotechnology, DNA sequences of interest can be cut and pasted together using recombinant DNA (rDNA) technology. It is possible to transport the recombinant DNA sequences into a suitable host cell via a vehicle called a vector. This technique has its own drawbacks as well.