What Is Gene Therapy?

Gene therapy is the process by which medical doctors and scientists attempt to correct certain genetic abnormalities and detrimental conditions caused by these genetic issues through the insertion of genes into a patient. Similarly, gene therapy can be achieved by the alteration of an existing gene. Still in the early stages of development, the theoretical implications of gene therapy include solutions for diseases ranging from cystic fibrosis to hemophilia, muscular dystrophy and sickle cell anemia.

Opposition to Gene Therapy

While there are many people who advocate further development of gene therapy methods for the obvious health implications, there are those who are opposed to gene therapy and the research needed to develop it. After all, the notion of what a genetic “defect” is could be broadly interpreted. While life-threatening diseases are certainly defects, opponents of gene therapy consider genetic alteration a path to eugenics and the genetic optimization of human subjects.

In spite of this opposition, there have been a number of successes with gene therapy. As early as 1990, patients with immune disorders have been successfully treated with the introduction of genetic material into the patient’s white blood cells. While the material needs to be constantly introduced to the patients and is not a permanent cure, gene therapy has been shown to drastically improve the quality of life for patients with this type of disease.

Methods For Gene Therapy

There are three types of gene therapy that are theoretically possible:

Gene Insertion: Gene insertion is the only possible version of gene therapy in use today. With gene insertion, genetic material is inserted into the patient via any number of vectors. If this insertion is successful, it becomes a fully functional protein. This can cause the targeted cells to produce additional types of proteins which can have the impact of reversing the conditions of certain diseases. However, the introduction of a protein into the current system of proteins can have unintended and wide-ranging consequences. That fact has caused researches to move towards other future forms of gene therapy.

Gene Modification: In this theoretical approach, existing DNA that presents a defect is physically altered to correct the defect. This is currently impossible given technological limitations today. However, if techniques were developed to accomplish this, the risk of disrupting the entire system is minimal, since no new proteins are introduced. This method has certain ethical implications, though, since alterations to any genetic protein would be possible, resulting in the ability to alter other characteristics present in the patient.

Gene Replacement: For many researchers, this technique is the ultimate goal of gene therapy development. With gene surgery, a defective DNA sequence could be removed, and a cloned copy of a normally functioning sequence would replace it. Until recently, this approach was held back due to difficulty with protein delivery vectors. However, recent advances have shown promise in certain situations with the replacement of faulty genes by working copies.

Reproductive Considerations

There is another element of gene therapy to consider. All of these approaches, even with the recent advantages in gene replacement, correct defects in a patient’s DNA. However, they do nothing for that patient’s offspring. While gene therapy is an easy choice for a patient that is faced with a life-threatening outcome, the effects on long-term viability for offspring who have had germ cells modified by gene therapy is yet undetermined. While this dilemma is not currently an issue, it may be in the near future.

Closing

Gene therapy is a promising branch of medical research that could yield tremendous results in the fight against genetic disease. The notion of eliminating genetic disorders is certainly a noble and worthwhile goal. However, care must be given to the ethical ramifications of advances in this field, and researchers need to more forwards deliberately and methodically.

About the Author

After finding an interest in the study of genetics during college, Derek Whitney’s life passion is to study and understand how genetic disease affects different individuals. When he is not researching or blogging on this matter, he enjoys working for GTL DNA, an international genetic testing company. In his spare time he enjoys working out, spending time with his girlfriend, and relaxing on the beach.