We define gene therapy as the introduction of new genes that replaces the defective gene, the main purpose of the procedure is to bring therapeutic benefits for the patients. In the process of gene therapy DNA and RNA are used.

By Ayesha Afzal


Human gene therapy can be seen under the spot light since many studies shows its effectuality against many life threatening diseases like AIDS, cancer, and some neurological disorders, as well as some common diseases like high blood pressure and diabetes, and some genetic disorders like cystic fibrosis.

Though many drugs or therapeutics based on genetic material (DNA and RNA) are under clinical trials as to ensure their reliability and to study their promising effectiveness against a wide range of diseases. Illumination of the human genome also helps us in identifying the genes that are of concern while studying the cause of the certain disease, that finally results in the development of   DNA or RNA based drugs for human gene therapy . The Human Genome Project was a landmark global scientific effort whose signature goal was to generate the first sequence of the human genome.  This Human genome project helps to ascertain genetic markers that are responsible for patient response to therapy, interactions of drug, and its possible side effects.

DNA based Therapeutics:

DNA based therapeutics include:

  • Plasmids
  • DNA-aptamers
  • DNAzymes


Plasmids are high molecular weight, double stranded DNA constructs that encode specific proteins. Plasmids only replicate in the host cell that’s why their mode of action requires access to cell’s internal structure i-e nucleus hence taking control over the efficiency of gene expression. In the early stages of development, plasmid-based gene therapy was used against those genetic disorders that are the result of single gene defect.. The first federally approved human gene therapy protocol was initiated in 1990 for the treatment of adenosine deaminase deficiency.

In developing countries where the conventional vaccines are not found available or expensive there is a need of such highly effective therapeutic agents, there fore pDNA vaccines are in demand and are expected to rise in near future .

DNA -aptamers:

DNA – Aptamers are nucleic acid molecules that can directly interact with proteins and are being investigated for clinical trials. Aptamers interpose with proteins that are involved in the   translation and transcription processes. Aptamers are preferred over antibodies in protein inhibition because they are highly specific , and non immunogenic. These DNA aptamers also found to have pharmaceutical stability.As a pharmacologic agent Aptamers come across some obstacles but this fact cant be denied that  the capability of binding to the target of both DNA and RNA aptamers is highly specific and selective, that’s why  it offers promising results and have bright future in therapeutics and clinical diagnosis.


DNA enzymes or DNAzymes  are some specifific DNA sequences that have catalytic activities , they are useful  while studying  reaction of RNA substrates . As far as a therapeutic effect is concerned they replace the RNA backbone chemistry with DNA motifs and this practice have come to shown biological stability. Upon injecting intramural injections in mice , DNA enzymes are found to be capable of suppressing tumors.


DNA based therapeutics have a bright future in the field of medicine and clinical diagnostics as in near future we need such products that are highly specific and give promising results, there are many diseases that require highly effective treatment for that purpose gene therapy or DNA based therapeutics plays major role as they target specific defective gene. Moreover vaccines like Pdna  vaccines are in demand as in areas where conventional vaccines are not available , we use these vaccines but we need to enhance the product yield of such vaccines or such dna based products so that they can also be made cost effective. In the era of modern sciences DNA based therapeutics play important role in terms of high specificity and providing us with the promising effectiveness against various dangerous diseases.