How can recombinant dna technology be a threat

Unless the rDNA enables the organism to use a substrate that the native population cannot metabolize, or enables the organism to reproduce at a higher rate, it is unlikely that the organism will survive. Due to many experiments of the type noted earlier, the lack of injuries to laboratory workers, and the lack of evidence of harm, 3,6 the restrictive requirements for working with rDNA have been somewhat relaxed.

It was readily noted that mammalian cells in culture "had no capacity for propagation outside the laboratory. As might be expected, there is much similarity between the regulation requirements of member states covering topics such as risk assessment, containment and control, disposal, etc.

There are clear edicts on expectations regarding biowaste treatment before disposal. The UK regulations state that Containment Level 1 activities e. The well-characterized nature of CHO cell lineages and the over two decades of safe use of these cell lines in large-scale production operations have exempted their categorization in the US from the containment levels BL1-LS to BL3-LS.

Hence, certain companies will inactivate CHO cell waste prior to disposal; others will not. Since CHO and other mammalian cells cannot persist in the environment, the only risk factor might be the existence of their chromosomal DNA and subsequent uptake by competent bacterial cells. Table 1 compares inactivation practices for large-scale operations using mammalian cells in certain states in the US and Europe.

Table 1. All companies use mammalian cell technology CHO or NS0 cell lines for the production of therapeutic proteins. Three different companies in west and east coast states of the US are represented. Information gathered through personal experiences and personal communications to the authors. Companies implementing inactivation methods are generally expected to use validated procedures.

Validation demonstrates that the inactivation method is suitable for purpose and removes the need to monitor for the GMM in waste streams after an inactivation event during routine operations. For certain classes of operation, usually Containment Level 2 and above, the capability of monitoring for the presence of GMM outside of the contained process is expected under UK and Irish guidelines previously mentioned. The need for this is dependent on practical feasibility and risk assessment outcome and is usually considered on a case-by-case basis.

Each year, the decay of pollen, leaves, fruit, and animals results in thousands of tons of DNA being released into the environment, 11 with measurable levels being reported in soils, 12 marine waters, freshwater lakes, rivers, and ponds. For a transfer to take place there must be a release of functional DNA, persistence of the DNA, and uptake by a competent cell.

A number of factors should be considered when questioning if eukaryotic genes in the natural environment can transfer to prokaryotic organisms. These factors include the fate of the DNA in the environment and its stability relative to the time required for a competent cell a cell capable of taking up DNA to take in the genetic material.

Other factors include the fate of the DNA in the prokaryotic cell, i. DNA, while abundant in the environment, is continuously under attack by physical shearing forces, chemical modifications, and microbially secreted nucleases.

It is often not available for transformation because it binds to solids and other matter Figure 2. Most bacteria in the environment are not normally in a competent state, and those that are have low transformation efficiencies. Under laboratory conditions optimized for transformation using bacterial plasmids, transformation of two ubiquitous soil bacteria was completed in minutes. The estimated half-life of DNA in wastewater is 1 to Thus, the probability of CHO cell DNA surviving long enough in wastewater to transform bacteria at ambient temperatures is very low.

There are barriers to expression of the transforming DNA if HGT does occur, thus preventing potential environmental impact.

These include the failure of DNA stabilization mechanisms within the cell as cited earlier; integration into the bacterial genome by homologous recombination or circularization to plasmid , the failure of accurate expression of the gene, and post-translational modification of the gene product. The principal barrier to successful transformation and expression is the lack of homology between the foreign DNA and the competent cell's DNA. An exponential decrease in recombination events with an increase in divergence of DNA sequence has been observed with enterobacteria and Bacillus spp.

Thus, despite the great amount of DNA that prokaryotes are exposed to and the great amount of time that prokaryotes and eukaryotes have coexisted, the incorporation of eukaryotic DNA into bacteria, as best can be determined, has been a very rare event. Recombinant CHO cell lines are used in the biotechnology industry for the production of many important biopharmaceutical and diagnostic products. Is there a significant risk that naturally occurring prokaryotic organisms in the waste stream or in the waste treatment plant will be transformed when exposed to cell culture waste containing viable CHO cells or their DNA?

A risk assessment of harm or damage resulting from a HGT event would consider the following:. The answer to the question of risk posed earlier is that while we cannot definitively discount all risk, the probabilities of damage due to horizontal transfer of eukaryotic DNA to prokaryotes is vanishingly small and is, thus, a negligible risk.

While there is some evidence that there has been HGT from eukaryotes to prokaryotes, this has been a very rare event. There are significant barriers to the transfer of eukaryotic DNA to prokaryotic organisms including lack of homology with the recipient's DNA complement and the degradation of DNA in the environment, particularly the rapid degradation in wastewater.

Therefore, the probability of genetic transfer of the free recombinant CHO cell gene sequences in process wastewater to bacteria is extremely remote due to a the rapid degradation of DNA in wastewater, b the low percentage of competent bacteria in the environment, c the low transformation efficiency of the competent bacteria that could be present and, d the lack of homology between bacterial host DNA and the mammalian cell DNA. The possibility that there would be an adverse environmental impact is more remote because even if the extremely unlikely transformation event occurred, there would have to be an expression of protein that would have to confer a selective advantage.

Without the selective pressure, the transferred gene would be lost due to random mutation or deletion. Thus, we conclude that the current best practice of containment as specified by the US NIH and the EU is effective in containing the risks involved in biotechnology development and large-scale production operations using CHO cells or other cell lines in the Containment Level 1 or GLSP categories.

Biofilm production was enhanced along with the production of pili and exopolysaccharide. The electron acceptor CL-1 produced biofilms that were 6-fold more conductive than wild-type biofilms when they were grown with electrode. This high fold conductivity lowered the potential losses in microbial fuel cells, decreasing the charge transfer resistance at the biofilm-anode surface and lowering the formal potential.

Potential energy was increased by lower losses [ ]. The fact that microbial cells are mostly used in the production of recombinant pharmaceutical indicates that several obstacles come into their way restricting them from producing functional proteins efficiently but these are handled with alterations in the cellular systems.

Common obstacles which must be dealt with are posttranslational modifications, cell stress responses activation, and instability of proteolytic activities, low solubility, and resistance in expressing new genes. The use of Escherichia coli in recombinant DNA technology acts as a biological framework that allows the producers to work in controlled ways to technically produce the required molecules through affordable processes [ 41 , ].

Recombinant DNA research shows great promise in further understanding of yeast biology by making possible the analysis and manipulation of yeast genes, not only in the test tube but also in yeast cells. Most importantly, it is now possible to return to yeast by transformation with DNA and cloning the genes using a variety of selectable marker systems developed for this purpose.

These technological advancements have combined to make feasible truly molecular as well as classical genetic manipulation and analysis in yeast. The biological problems that have been most effectively addressed by recombinant DNA technology are ones that have the structure and organization of individual genes as their central issue [ , ]. Recombinant DNA technology is recently passing thorough development which has brought tremendous changes in the research lines and opened directions for advanced and interesting ways of research for biosynthetic pathways though genetic manipulation.

Actinomycetes are being used for pharmaceutical productions, for example, some useful compounds in health sciences and the manipulation of biosynthetic pathways for a novel drugs generation. These contribute to the production of a major part of biosynthetic compounds and thus have received immense considerations in recombinant drugs designing. Their compounds in clinical trials are more applicable as they have shown high level activity against various types of bacteria and other pathogenic microorganisms.

These compounds have also shown antitumor activity and immunosuppressant activity [ ]. Recombinant DNA tech as a tool of gene therapy is a source of prevention and cure against acquired genetic disorders collectively. DNA vaccines development is a new approach to provide immunity against several diseases. In this process, the DNA delivered contains genes that code for pathogenic proteins.

Human gene therapy is mostly aimed to treat cancer in clinical trials. Research has focused mainly on high transfection efficacy related to gene delivery system designing. Transfection for cancer gene therapy with minimal toxicity, such as in case of brain cancer, breast cancer, lung cancer, and prostate cancer, is still under investigation. Also renal transplantation, Gaucher disease, hemophilia, Alport syndrome, renal fibrosis, and some other diseases are under consideration for gene therapy [ ].

Recombinant DNA technology is an important development in science that has made the human life much easier. In recent years, it has advanced strategies for biomedical applications such as cancer treatment, genetic diseases, diabetes, and several plants disorders especially viral and fungal resistance.

The role of recombinant DNA technology in making environment clean phytoremediation and microbial remediation and enhanced resistace of plants to different adverse acting factors drought, pests, and salt has been recognized widely. The improvements it brought not only in humans but also in plants and microorganisms are very significant. The challenges in improving the products at gene level sometimes face serious difficulties which are needed to be dealt for the betterment of the recombinant DNA technology future.

In pharmaceuticals, especially, there are serious issues to produce good quality products as the change brought into a gene is not accepted by the body. Moreover, in case of increasing product it is not always positive because different factors may interfere to prevent it from being successful.

Considering health issues, the recombinant technology is helping in treating several diseases which cannot be treated in normal conditions, although the immune responses hinder achieving good results. The integration of incoming single-stranded DNA into the bacterial chromosome would be carried out by a RecA-dependent process. This requires sequence homology between both entities, the bacterial chromosome and incoming DNA. Stable maintenance and reconstitution of plasmid could be made easy.

The introduction of genetic material from one source into the other is a disaster for safety and biodiversity. There are several concerns over development of genetically engineered plants and other products.

Further, concerns exist that genetic engineering has dangerous health implications. Thus, further extensive research is required in this field to overcome such issues and resolve the concerns of common people. The authors declare that there is no conflict of interests regarding the publication of this paper. The corresponding author is thankful to Xuan H. This is an open access article distributed under the Creative Commons Attribution License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Academic Editor: Wenqin Wang. Received 10 Aug Revised 21 Oct Accepted 06 Nov Published 08 Dec Abstract In the past century, the recombinant DNA technology was just an imagination that desirable characteristics can be improved in the living bodies by controlling the expressions of target genes.

Introduction Human life is greatly affected by three factors: deficiency of food, health problems, and environmental issues. Recombinant DNA Technology Recombinant DNA technology comprises altering genetic material outside an organism to obtain enhanced and desired characteristics in living organisms or as their products. Figure 1. Illustration of various applications of recombinant DNA technology.

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Paul Berg talks about the "Moratorium Letter. Paul Berg talks about why experiments with recombinant DNA set off a firestorm of controversy, including a moratorium on further experimentation with rDNA. Berg describes colleague Bob Pollack's outrage at this. Paul Berg speaks about Herbert Boyer's research into the process by which an organism, such as a bacterium, can recognize and destroy foreign DNA.