What is the Difference Between PCR and Cloning

The main difference between PCR and cloning is that PCR produces millions of copies of a specific DNA, whereas cloning produces individuals with identical DNA.

PCR and cloning are two techniques that involve the production of a large number of identical DNA copies. Both processes are important in recombinant protein production.

Key Areas Covered

1. What is PCR
    – Definition, Characteristics, Importance
2. What is Cloning
    – Definition, Characteristics, Importance
3. Similarities Between PCR and Cloning
    – Outline of Common Features
4. Difference Between PCR and Cloning
    – Comparison of Key Differences

Key Terms

PCR, Polymerase Chain Reaction, Cloning

What is PCR

PCR or polymerase chain reaction is the laboratory technique for the production of millions of copies of specific DNA in vitro. It was developed by Kary Mullis in 1983. The most significant feature of PCR is that it relies on thermal cycling. Therefore, it permits different temperature-dependent reactions to occur, including DNA melting and enzyme-driven DNA polymerization. On the other hand, the two main reagents used in PCR are the DNA primers, which are complementary to the target sequence, and a heat-stable DNA polymerase such as Taq polymerase, isolated from the thermophilic bacterium Thermus aquaticus. Meanwhile, the forward and reverse PCR primers flank the region to be polymerized on the DNA fragment.

Figure :1 PCR

Furthermore, PCR is important for selective DNA isolation, amplification, and quantification of DNA, infectious disease diagnosis, forensic applications, and research applications. Another feature of PCR is the rapid amplification of DNA in vitro. The products of PCR are important for sequencing, cloning, and analysis. In addition, qPCR is important for the quantification of gene expression in cancer, microbes, and other disease states.

What is Cloning

Cloning is the process of producing individual organisms with identical DNA. There are four types of cloning: natural cloning, molecular cloning, cell cloning, and organism cloning. Generally, asexual reproduction in plants, fungi, and bacteria is a method of cloning. Asexual reproduction produces another individual with similar genetic characteristics to the parent organism. In comparison, molecular cloning is the process of producing multiple molecules. Normally, it involves the production of multiple copies of DNA fragments, which is important for studying the gene and its expression.

Figure 2: Natural Cloning

Moreover, cell cloning is the process of cloning cells. There are two types of cell cloning: cloning of unicellular organisms and stem cell cloning. Unicellular organisms such as bacteria and yeast are cloned to produce cell populations with similar genetics. Generally, it is important in the production of recombinant proteins such as vaccines and antibiotics. Stem cell cloning, on the other hand, is important for research and therapeutic purposes. In addition, organism cloning is the process of creating new multicellular organisms that is genetically identical to one another.

Similarities Between PCR and Cloning

• PCR and cloning are two techniques involved in the production of a large number of identical copies of DNA.
• Both techniques are important in the production of recombinant proteins.

Difference Between PCR and Cloning

Definition

PCR refers to a laboratory technique for rapidly producing (amplifying) millions to billions of copies of a specific segment of DNA while cloning refers to the process of generating a genetically identical copy of a cell or an organism.

Significance

PCR produces millions of copies of a specific DNA while cloning produces a large number of individuals with identical DNA.

Production of DNA Copies

Moreover, PCR produces DNA copies in vitro while cloning produces DNA copies in vivo.

Requirements

PCR requires Taq DNA polymerase for the amplification of DNA while cloning requires an organism.

Applications

PCR is important in diagnostics, forensics, and genetic testing while cloning is important for the production of proteins, antibiotics, and vaccines.

Conclusion

In brief, PCR and cloning are two techniques involved in the production of a large number of copies of a specific DNA. Generally, PCR produces millions of copies of a specific DNA in vitro. It also requires Taq DNA polymerase for the amplification of DNA. PCR is also important in diagnostics, forensics, and genetic testing. In comparison, cloning is the production of a large number of individuals with identical DNA. The amplification of DNA occurs in vivo in cloning. Importantly, cloning is useful for the production of proteins, vaccines, and antibiotics as well. Therefore, the main difference between PCR and cloning is the amplification of DNA.

References:

1. “Polymerase Chain Reaction (PCR) (Article).” Khan Academy, Khan Academy
2. “Cloning.” National Geographic Society, 

Image Courtesy:

1. “Quakingfallcolors” By Beeblebrox – Own work (CC BY-SA 3.0) via Commons Wikimedia
2. “Polymerase chain reaction-en” By Enzoklop – Own Work (CC BY-SA 4.0) via Commons Wikimedia