Why recombinant dna technology is important

Other compounds, for example, proteins can also be easily separated from DNA by altering the concentration of salt in the extraction buffer. Restriction endonucleases are a group of enzymes derived primarily from bacteria. Although there are several different types of restriction enzymes , those most useful for rDNA technology recognize specific short sequences in DNA and cleave the DNA at that site to produce cohesive sticky or blunt-ended fragments Figure 2.

More than different restriction enzymes have been identified and can be purchased commercially. Thus, one may ask the question, how often does a restriction enzyme cut within a genomic sequence?

It is not possible to give an exact answer for this question. However, let us assume that there are 4 bases on any strand of DNA. Assuming you have isolated genomic DNA from maize, and you want to digest it with a restriction enzyme that cuts every 4, 4, bp, how many fragments will you obtain? To answer this question, you need to have an idea of the size of the genome of the plant you are working with. The approximate size of the maize genome is 2,,, bp. Note that nucleotide distribution is not always random and thus frequency may be different for given DNA.

Also, methylation of specific bases in genomic DNA can prevent cleavage at some site. The only physical features of nucleic acid fragments that are routinely used for their characterization are their size and nucleotide sequence.

Molecular weight of DNA is most conveniently evaluated by electrophoresis in agarose gels. Agarose forms a gel by hydrogen bonding when cooled from the melted state. Pore size, which affects rate of movement of DNA fragments of a given size, depends on the concentration of agarose.

The gel is submerged in electrolyte solution; sample is loaded into wells on one end and current is applied to facilitate movement of DNA fragments. Since DNA is negatively charged it will migrate in the electrical field. Fragments separate according to size. Polymerase chain reaction PCR is a method by which millions of copies of a DNA fragment are produced in a test tube in a matter of minutes or a few hours. Once the sequence of a particular gene is known, it becomes possible to use PCR to isolate that gene from any DNA sample.

Recall in Lesson on Gene Transcription you learned that at the genomic level a gene is made up of regulatory sequences, coding, and non-coding sequences. Thus, if the goal is to use PCR to isolate both regulatory and non-regulatory sequences of a gene, the approach would be to use DNA as the starting material.

Alternatively, PCR products may be cloned directly into a T-vector without restriction digestions in E. After cloning into E. Like all other biochemical processes, DNA synthesis by PCR is not a perfect process, and occasionally the polymerase enzyme will add an incorrect base to the growing DNA strand. He also discovered with Herbert Boyer a restriction enzyme that could cleave a circular plasmid at a single site. This laid the foundation for their joint experiment in which demonstrated the feasibility of combining and replicating genetic information from different species.

Their experiment involved inserted a gene for frog ribosomal RNA into bacterial cells which then expressed the gene. Three patents were taken out on their technique. These paved the way to the rise of new start-up biotechnology companies, founded on the back of the promise of genetic engineering for generating new therapeutic products.

This they did by combining a gene for frog ribosomal RNA with a bacterial plasmid which was then put into a strain of E-coli for expression. Based on this technique Boyer helped found Genentech, the first biotechnology company dedicated to commercialising recombinant DNA. This he did in in collaboration with Robert Swanson. He also spearheaded efforts for the scientific governance of recombinant DNA and genome editing technologies.

From to Swanson was Chief Executive and Director of the company and played an instrumental role in leading it to become the first major biotechnology company to show a profit and go public. It has the advantage that it can be easily grown in E Coli and is not pathogenic except in the case of bacteria. Lederberg's discovery paved the way to understanding the transfer of genetic material between bacteria, the mechanisms involved in gene regulation and how piece of DNA break apart and recombine to make new genes.

He published his experiment in the Journal of Biological Chemsitry in May Louis Werner Arber, Swiss microbiologist and geneticist, and his doctoral student Daisy Dussoix proposed that bacteria produce restriction and modification enzymes to counter invading viruses. Arber, 'Host-controlled modification of bacteriophage', Annual Review Microbiology, 19 , They found that bacteria protect themselves against invading viruses by producing two types of enzymes.

One cut up the DNA of the virus and the other restricted its growth. Arber believed these two enzymes could provide an important tool for cutting and pasting DNA, the method now used in genetic engineering. Its discovery was pivotal to the development of recombinant DNA.

The two scientists announced their achievement to a press conference as part of an effort to increase the American public's appreciation of government funded scientific work. It, however, generated debate about whether life should be created in a test tube. The achievement was an important stepping stone to the development of recombinant DNA. Restriction enzymes are now workhorses of molecular biology. They are essential in the development of recombinant DNA and were pivotal to the foundation of the biotechnology industry.

The enzyme was simultaneously discovered independently by Howard Temin and David Baltimore. Temin made the discovery while working on Rous sacoma virions and Baltimore was working on the poliovirus and vesicular stomatis virus. The discovery laid the foundations for the the disciplines of retrovirology and cancer biology and ability to produce recombinant DNA. Following this Berg self-imposed a moratorium on experiments in his laboratory involving the cloning of SV40 in E-Coli.

The session was chaired by Norton Zinder. The discussion set the stage for the subsequent Asilomar Conference in which led to the first guideline for experiments with genetic engineering.

It was generated by cutting DNA with a restriction and then using ligase to paste together two DNA strands to form a hybrid circular molecule. They managed to splice sections of viral DNA and bacterial DNA with the same restriction enzyme to create a plasmid with dual antibiotic resistance. The technique showed it was possible to reproduce recombinant DNA in bacteria.

It argued for the establishment of an advisory committee to oversee experimental procedures to evaluate the potential biological hazards of recombinant DNA molecules and develop procedures to minimise the spread of such molecules within human and other populations.

In addition to the moratorium the conference established several principles for safely conducting any genetic engineering. Containment was considered essential to any experimental design, such as the use of hoods, and the use of biological barriers was suggested to limit the spread of recombinant DNA.

This included using bacterial hosts that could not survive in natural environment and the use of vectors plasmids, bacteriophages and other viruses that could only grow in specified hosts. The conference also called for a moratorium on genetic engineering research in order to have time to estimate the biohazard risks of recombinant DNA research and develop guidelines.

It was the first biotechnology company established specifically dedicated to commercialising recombinant DNA. Its founding marked the start of what was to become a burgeoning biotechnology industry.

Arber was the first to discover the enzymes; Smitth demonstrated their capacity to cut DNA at specific sites and Nathans showed how they could be used to construct genetic maps. With their ability to cut DNA into defined fragments restriction enzymes paved the way to the development of genetic engineering. This would free them up from a dependence on rodents for producing monoclonal antibodies.

He publishes the idea in C. It was published in J R Arrand, L. The vaccine was made using HBsAg cloned in yeast. Each team had developed their techniques separate from each other. The second team consisted of Sherie Morrison and colleagues at Stanford University together with Gabrielle Boulianne and others at the University of Toronto. The vaccine was regarded as a breakthrough because it was made from a genetically engineered sub-particle of the virus.

This made it much safer than the original vaccine which used the virus sub-particle sourced from the blood of hepatitis B sufferers. The vaccine heralded a new era for the production of vaccines and is a major weapon against one of the most infectious diseases. The development of interferon rested on the application of both genetic cloning and monoclonal antibodies.

It is accomplished with technology developed by Greg Winter. The two scientists isolated a gene that causes cancer in many mammals, including humans, and inserted it into fertilised mouse eggs.

The aim was to genetically engineer a mouse as a model for furthering cancer research and the testing of new drugs. It was the first animal ever given patent protection in the USA. The drug helps suppress the replication of the hepatitis B virus.

Application of recombinant DNA technology genetically modified organisms to the advancement of agriculture, medicine, bioremediation and biotechnology industries. J Appl Biotechnol Bioeng. DOI: Download PDF. Genetic engineering has always been a topic of controversy as the balance it aims to reach between the benefits accrued to humans and attendant ethical considerations is open to debate.

In each of the diverse fields of agriculture, medicine, bioremediation and biotechnology concerns vary in a discipline-specific manner. However, the principal source of apprehension often involves the ecological impact, real or perceived, of the use of recombinant DNA technology, in particular the release of genetically modified organisms into the environment.

In this short review, pressing issues are highlighted, the potential severity of the negative effects is addressed, and methods for overcoming these are indicated. Keywords: biotechnology, genetic engineering, genetically modified organism, recombinant DNA, transgenic Introduction History.

The use of recombinant r- DNA technology to produce genetically engineered organisms started in the early s with the pioneering transfer of genes between bacteria of the same Escherichia coli species.

This facilitated the widespread commercial availability of insulin at a price affordable to patients with the metabolic disorders types 1 and 2 diabetes mellitus, who either fail to produce or to metabolize sufficient insulin. This proof of principle demonstration of the translational medical benefits of genetic modification pioneered a trend in biotechnology for molecular cloning methods to transfer genes expressing desirable traits into another host organism thereby producing favourable characteristics.

This now involves both prokaryotes such as bacteria comparatively routine to modify genetically by r-DNA technology and eukaryotes including yeast, plants, insects and mammals comparatively complex to manipulate via r-DNA technology. The latter is a waste management technique that deliberately introduces GMOs into a site to neutralize environmental contaminants breaking down hazardous substances into less toxic or non-toxic compounds with the aim of cleansing thoroughly, quickly and cheaply polluted soil or water.

For each use there will be costs as well as benefits, all of which should be considered rationally when coming to an informed decision whether to use genetic modification on an industrial scale. In agriculture development of genetically modified crops with a purpose to improve both yield and resistance to plant pests or herbicides seems to have gained a degree of public acceptance and is already practised in a commercial context in several countries.

This was developed in to express the trait of delayed softening of tomato flesh as a practical means to minimize post-harvest crop losses. Nevertheless, the introduction of a genetically modified fruit paved the way for use of GMOs in food and today genetic modification is widespread. The introduction of pest-resistant brinjal also known as eggplant or aubergine was met with criticism in some countries, in contrast to the concurrent popularity of pest-resistant cotton.

Both attempts at implementation followed incorporation of the identical crystal protein gene Cry1Ac from the soil bacterium Bacillus thuringiensis Bt into the genome of the host plant expression of which synthesizes so-called Bt toxins that confer resistance to predation by lepidopteran insects.

However, of the two uses as a food and as clothing the one which caused anxiety among the general public involved human consumption. The benefits to humans of using Bt toxin should be stressed in an attempt to overcome the initial unpopularity of consuming Bt-brinjals in developing countries such as India, 7 Bangladesh 8 and Philippines.

Drug delivery systems in medicine that are based on bacterial or viral hosts could prove hazardous if either the organism is genetically unstable and converts to a pathogenic type or if purification is incomplete.

Consequently, identification of a preferred system to safely and efficiently deliver an altered gene of choice has become a priority as the technology advances from development and laboratory research to clinical translational trials. Pseudomonas putida and Nitrosomonas europaea are the organisms which are typically utilized in bioremediation. The objective is to isolate the original genes located in these bacteria that promote bioremediation, then modify and incorporate them into a suitable host to be used as a bioremediation agent usually E.

Hence, stringent monitoring of in situ bioremediation is essential. This achieves the purposeful generation of antibiotic-resistant organisms which, if mishandled, could become problematic under natural conditions. An appreciable biotechnological success and novel commercial application is the production of genetically modified fluorescent zebrafish, Danio rerio, and similar species using genes encoding glowing characteristics. In the event of release, inadvertent or deliberate, into the environment the survival capacity of these constantly fluorescent fish is markedly reduced due to increased vulnerability to predation compared to wild type fish; thus, the risk of sustained ecological impact is considered to be marginal.

It showed impressive results for incurable autosomal recessive dystrophies such as congenital blindness and Leber congenital amaurosis LCA. After the treatment silencing of the transgene as a result of methylation of the viral promoter caused the severity of infection that leaded to the death of patient [ 73 ].

Many different cancers including lung, gynecological, skin, urological, neurological, and gastrointestinal tumors, as well as hematological malignancies and pediatric tumors, have been targeted through gene therapy. Inserting tumor suppressor genes to immunotherapy, oncolytic virotherapy and gene directed enzyme prodrug therapy are different strategies that have been used to treat different types of cancers. The p53, a commonly transferred tumor suppressor gene, is a key player in cancer treating efforts.

In some of the strategies, p53 gene transfer is combined with chemotherapy or radiotherapy. The most important strategies that have been employed until now are vaccination with tumor cells engineered to express immunostimulatory molecules, vaccination with recombinant viral vectors encoding tumor antigens and vaccination with host cells engineered to express tumor antigens [ 19 ]. A demonstration of these vectors through proper assaying was significant for transduction improvement and more progeny of the virus were produced in HCC.

A higher level of transgenic expression was mediated and an enhanced antitumor effect was observed on in vitro HCC cells while keeping the normal cells protected against cytotoxicity. Tumor growth was also inhibited by utilizing this technology [ 74 ]. Cancer gene therapy has become more advanced and its efficacy has been improved in recent years [ 75 ]. Treatment of cardiovascular diseases by gene therapy is an important strategy in health care science.

In cardiovascular field, gene therapy will provide a new avenue for therapeutic angiogenesis, myocardial protection, regeneration and repair, prevention of restenosis following angioplasty, prevention of bypass graft failure, and risk-factor management.

Its treatment requires stem cells transplantation; in case matched donors are unavailable the treatment is carried out through infusion of autologous HSPCs modified ex vivo by gene therapy [ 76 ]. Metastatic cancer can be regressed through immunotherapy based on the adoptive transfer of gene-engineered T-cells. Accurate targeting of antigens expressed by tumors and the associated vasculature and the successful use of gene engineering to retarget T-cells before their transfer into the patient are mainly focused on in this therapy [ 77 ].

T-cells in cancer patients can be modified by recombining the genes responsible for cancer-specific antigens recognition, resistance to immunosuppression, and extending survival and facilitating migration to tumors [ 78 ]. Fusion between the genes echinoderm microtubule-associated protein like 4 EML4 and anaplastic lymphoma kinase ALK is generated by an inversion on the short arm of chromosome confers sensitivity to ALK inhibitors.

Wnt signaling is one of the key oncogenic pathways in multiple cancers. Targeting the Wnt pathway in cancer is an attractive therapeutic approach, where LGK potently inhibits Wnt signaling, has strong efficacy in rodent tumor models, and is well-tolerated.

Head and neck cancer cell lines with loss-of-function mutations in the Notch signaling pathway have a high response rate to LGK [ 80 ]. Codon-optimized gene, on the basis of coding sequence of the influenza virus hemagglutinin gene, was synthesized and cloned into a recombinant modified vaccinia virus Ankara MVA. Immunization with MVA-H7-Sh2 viral vector in ferrets proved to be immunogenic as unprotected animals that were mock vaccinated developed interstitial pneumonia and loss of appetite and weight but vaccination with MVA-H7-Sh2 protected the animals from severe disease [ 81 ].

Viral gene therapy is one of the leading and important therapies for head and neck cancer. Tumor-associated genes are targeted by viruses, and p53 gene function was targeted through such therapy at first.

Cancer cells can be destroyed by oncolytic viruses through viral replication and by arming with therapeutic transgenes [ 82 ]. High density lipoprotein gene ABCA1 mutation in cells can make the cells be differentiated into macrophages. Gene knockouts in embryonic stem cells enhance the capability of cells to be differentiated into macrophages and specifically target the desired pathogens.

The allele replacements in this case will assist in studying protein coding changes and regulatory variants involved in alteration of mRNA transcription and stability in macrophages [ 83 ]. Plant systems have been recently used for the expression and development of different antibodies and their derivatives. Most importantly, out of many antibodies and antibody derivatives, seven have reached to the satisfactory stages of requirements. Oral pathogen responsible for decay of a tooth known as Streptococcus mutants, can be recognized by this antibody.

A monoclonal antibody called T Antibodies from both sources have been shown to prevent vaginal HSV-2 transmission in mice after applying topically; if worked similarly in humans it would be considered as inexpensive and affective prevention against diseases transmitted through sexual interactions [ 86 — 88 ].

Administration of the antibody to mice resulted in the production of anti-idiotype antibodies that are able to recognize 38C13 cells, which help to protect the mice against with injected lymphoma cells, is a lethal challenge [ 89 , 90 ]. Unique markers recognizing enzymes could be produced through this system, most affectively the surface markers of a malignant B-cells to work as an effective therapy for non-Hodgkin lymphoma like diseases in human [ 61 ].

A monoclonal antibody known as PIPP is specific for human chorionic gonadotropin recognition. The production of full-length monoclonal antibody and scFv and diabody derivatives was made possible in plants through transgenesis and agroinfiltration in tobacco transformed transiently [ 91 ]. Testosterone production by stimulated hCG can be inhibited by each of these antibodies in cells cultured by LEYDIG and uterine weight gain could be delayed in mice, through which hCG activity is checked.

Diagnosis and therapy of tumors can be carried out with the help of antibodies [ 61 ]. Complex system of drug metabolizing enzymes involved in the drug metabolism is crucial to be investigated for the proper efficacy and effects of drugs.

Comparatively conventional vaccines have lower efficacy and specificity than recombinant vaccine. A fear free and painless technique to transfer adenovirus vectors encoding pathogen antigens is through nasal transfer which is also a rapid and protection sustaining method against mucosal pathogens. This acts as a drug vaccine where an anti-influenza state can be induced through a transgene expression in the airway [ 74 ]. FSH is considerably a complex heterodimeric protein and specified cell line from eukaryotes has been selected for its expression.

Assisted reproduction treatment through stimulating follicular development is an achievement of recombinant DNA technology. A large number of patients are being treated through r-FSH. Most interestingly r-FSH and Luteinizing Hormone LH recombination was made successful to enhance the ovulation and pregnancy [ 94 , 95 ].

As an important component of alternative medicine, traditional chines medicines play a crucial role in diagnostics and therapeutics. These medicines associated with theories which are congruent with gene therapy principle up to some extent.

These drugs might be the sources of a carriage of therapeutic genes and as coadministrated drugs. Transgenic root system has valuable potential for additional genes introduction along with the Ri plasmid. It is mostly carried with modified genes in A. The cultures became a valuable tool to study the biochemical properties and the gene expression profile of metabolic pathways. The intermediates and key enzymes involved in the biosynthesis of secondary metabolites can be elucidated by the turned cultures [ 96 , 97 ].

Improvement in nutritional values of strawberries has been carried through rolC gene. This gene increases the sugar content and antioxidant activity. Glycosylation of anthocyanins requires two enzymes glycosyl-transferase and transferase.

Some nutrition related genes for different components in strawberry including proanthocyanidin, l-ascorbate, flavonoid, polyphenols, and flavonoid are important for improving the component of interest through genetic transformation. By specific transformation, these genes can enhance the production and improve the quality.

All these mentioned compounds have medical values [ 98 ]. Genetic engineering has wide applications in solving the environmental issues. The release of genetically engineered microbes, for example, Pseudomonas fluorescens strain designated HK44, for bioremediation purposes in the field was first practiced by University of Tennessee and Oak Ridge National Laboratory by working in collaboration [ 99 , ]. The engineered strain contained naphthalene catabolic plasmid pUTK21 [ ] and a transposon-based bioluminescence-producing lux gene fused within a promoter that resulted in improved naphthalene degradation and a coincident bioluminescent response [ ].

HK44 serves as a reporter for naphthalene bioavailability and biodegradation whereas its bioluminescence signaling ability makes it able to be used as an online tool for in situ monitoring of bioremediation processes [ ]. The production of bioluminescent signal is detectable using fiber optics and photon counting modules [ ]. Genetic engineering has been widely used for the detection and absorption of contaminants in drinking water and other samples.

The At PHR1 transgenic plants with enhanced Pi absorption ability can possibly facilitate effective phytoremediation in polluted aquatic environments [ ].

This plasmid was named pSPB and was used for transformation [ ] in Petunia and Verbena using Agrobacterium tumefaciens [ ]. Plant metabolism processes identify their importance to use for remediating the environmental pollutants. Some of the chemicals are not prone to be degraded or digested. TNT is only partially digested in which the nitrogen further reacts with oxygen to form toxic superoxide. To overcome this issue, the gene responsible for monodehydroascorbate reductase is knocked out which increases the plant tolerance against TNT.

Fine-tuning enzymatic activity and knockout engineering together enhance the plant responses to toxic metals. Phytochelatin synthase, a heavy metal binding peptides synthesizing enzyme, revealed a way to enhance tolerance against heavy metals through enzymatic activity attenuation [ ].

Recombinant DNA technology has proven to be effective in getting rid of arsenic particles that are considered as serious contaminants in soil.

Seeds of plants genetically engineered with PvACR3 can germinate and grow in the presence of higher than normal quantity of arsenate [As V ] which are generally lethal to wild-type seeds. Arsenic As is reduced by As reductase present in A. Phytochelatins restrict the arsenic movement in root cells and phloem companion cells. In plants, brassino-steroid BR is involved in regulating physiological and developmental processes.

Its activity is started with triggering phosphorylation or dephosphorylation cascade [ ]. Recent biotechnological approaches for bioremediation include biosorption, phytostabilization, hyperaccumulation, dendroremediation, biostimulation, mycoremediation, cyanoremediation, and genoremediation, which majorly depend on enhancing or preventing specified genes activities.

However, the challenges in adopting the successful technique cannot be ignored [ ]. Several microorganisms, specifically cyanobacteria, mediate hydrogen production, which is environmental friendly energy source.

The specific production is maintained by utilizing the required enzymes properly as these enzymes play a key role in the product formation. But advanced approaches like genetic engineering, alteration in nutrient and growth conditions, combined culture, metabolic engineering, and cell-free technology [ — ] have shown positive results to increase the hydrogen production in cyanobacteria and other biofuels [ 3 , 4 ]. The commercialization of this energy source will keep the environment clean which is not possible by using conventional energy sources releasing CO 2 and other hazardous chemicals [ ].

Also cyanobacteria can be engineered to make them able to convert of CO 2 into reduced fuel compounds. This will make the carbon energy sources harmless to environment. This approach has been successful for vast range of commodity chemicals, mostly energy carriers, such as short chain and medium chain alcohols [ ]. The conductive biofilms of Geobacter sulfurreducens are potential sources in the field in renewable energy, bioremediation, and bioelectronics.

Deletion of PilZ genes encoding proteins in G. CL-1ln is specified for the strain in which the gene GSU was deleted. 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.

Article of the Year Award: Outstanding research contributions of , as selected by our Chief Editors. Read the winning articles. Journal overview. Special Issues. 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. Table 1.