Recombinant DNA Technology deals with joining DNA molecules from two separate species, which carry the desired characteristics of a particular organism. The recombined DNA molecules are inserted into the host organism to produce new genetic combinations that contribute value to science, medicine, agriculture, and industry. The gene is the focus of all genetics, and the fundamental objective of all geneticists in the laboratory is to isolate, characterize, and manipulate genes. Recombinant DNA technology is mainly centered on two other technologies, which are cloning and DNA sequence. 

When the cloning technology is undertaken, it is to obtain the clone of one specific gene or DNA sequence of interest. After the cloning has been done, the clone is found and isolated among other members of the large collection of clones. The nucleotide is determined after a segment of the DNA has been cloned. Recombinant DNA technology has been effectively used to produce various human proteins in microorganisms, such as insulin and growth hormone used in treating diseases. 

Recombinant DNA is a biomacromolecule, mainly endogenous proteins. It gives a variety of special considerations and concerns, such as whether the produced molecule through recombinant DNA technology is biologically equivalent to the naturally occurring ones. Or, as they are mostly proteins, will they result in immunogenic reactions that would limit their usefulness.

To produce a large copy number of recombinant DNA with polymerase chain reaction (PCR), molecular cloning is the laboratory technique of the protein expression company. The process of these molecular cloning consists of seven steps.

Molecular Cloning Process 

The process of molecular cloning consists of seven steps which are

1. Choice of host organism and cloning vector: the host organism of recombinant DNA technology is majorly bacteria, and the choice of cloning vector has to do with the choice of the host organism, the size of foreign DNA fragment, and the level of expression. 
2. Preparation of vector DNA: to make compatible ends with foreign DNA fragments, the cloning vector will be digested with restriction enzymes.
3. The cloned preparation of DNA: to generate compatible ends with the cloning vector, the desired DNA fragment meant to be cloned can be amplified by polymerase chain reaction (PCR) and digested with the reaction enzymes.
4. Recombinant DNA creation: treating with DNA ligase, the digested cloning vector and polymerase chain reaction (PCR) fragment in protein production cro are ligated.
5. Recombinant DNA introduction into the host organism: The recombined DNA molecules will be transformed into bacteria to obtain many copies. 
6. Transformed organism selection: A selectable marker such as antibiotic resistance can be used to select the transformed bacteria in a culture.
7. Desired DNA clone screening: to screen the clones of the desired DNA fragments, a blue-white screening system, PCR, restriction fragment analysis, nucleic acid hybridization, DNA sequencing, and antibody probes can be used. 

The usefulness of Recombinant DNA Technology

Recombinant DNA has played a significant role in its use in science laboratories. Through the techniques of recombinant DNA, bacteria have been created. They are capable of synthesizing human insulin, human growth hormone, alpha interferon, hepatitis B vaccine, and other substances that are medically inclined. Recombinant DNA technology serves other usefulness in gene therapy that sees to the introduction of a normal gene into an individual’s genome to repair a mutation that causes genetic disease. 

It can obtain specific DNA clones using recombinant DNA technology that makes it easy and possible to add one organism’s DNA to another’s genome. The added gene is a transgene and can be passed to progeny as a new component of the genome. And the resulting organism that is responsible for carrying the transgene is called a transgenic organism or a Genetically Modified Organism (GMO). Based on this, a designer organism is made and contains some specific change required for an experiment in basic genetics or improvement of some commercial strain. 

The Application of Recombinant DNA

There are diverse applications in gene cloning in the protein production service. And it has proven to be useful in the mapping out of the human genome, the creation of transgenic animals, and the development of insect-resistant crops. Its application is also essential to the genetic tests carried out in forensic science and archaeology. It is also useful in tests for determining hereditary disease and paternity. Custom recombinant protein production technology also forms the backbone of hepatitis and human immunodeficiency virus (HIV) diagnostic tests. Recombinant DNA technology is important for producing vaccines and protein therapies like human insulin, interferon, and human growth hormone. Recombinant DNA technology is also used to produce clotting factors for treating hemophilia and developing gene therapy.

Conclusion

Recombinant DNA technology is crucial in introducing the desired characteristics to organisms. And bacteria are used as models in recombinant DNA technology due to many factors such as easy growth, manipulation, rapid cell division, simplicity, and ability to select and screen transformants.