How to Create Gene Therapy Treatment Specific to a Patient's Needs

Now, imagine medicine itself not as one-size-fits-all, but as a treatment designed just for you, based on your body’s own unique instructions. That’s the concept behind personalized gene therapy. Researchers are trying to develop ways to repair or replace misbehaving genes that lead to disease, and their goal is to make these therapies so precise that they address the underlying source of the trouble unique to one person. It’s kind of like getting a software update to your body’s operating system, except instead of fixing a bug on your phone, it’s fixing a bug that’s making you ill.

Developing a one-of-a-kind gene therapy starts with a thorough analysis of your blood. Researchers must know specifically what is going awry at the level of the DNA. They often begin with a genetic test to learn exactly which gene mutation is causing your illness, which requires testing some of your blood or other tissues. It’s just as if detectives found a clue that points to the problem. People with the same disease might have different mutations in the same gene or mutations in different genes altogether. It is essential to identify the exact genetic issue because the treatment will have to be tailored to the error.

Once the responsible gene is identified, the second challenge is: How do you get the fix where it needs to go? Enter the fix known as a “vector.” Scientists often use altered viruses as vectors. Viruses are so good at slipping into cells. That’s what gene therapy has to do: arrive inside cells that are often used as vectors to carry DNA. Yet these viruses are specifically engineered in the lab so that they cannot cause disease. They function as little delivery trucks, shuttling the corrected gene into your cells. Other delivery systems, like nanoparticles (tiny surface-coated particles that can carry the genetic material), are also being investigated by researchers. The trick is to guide these delivery trucks to the right spot inside your body and into the right cells, where the faulty gene is wreaking havoc.

The gene that actually does the therapeutic work is like the corrected software code. The idea is to build a working copy of the gene that is missing or defective in the patient. This gene is subsequently inserted into the vector. The idea here is that this new gene should be able to gear itself up inside your cells and then get to work properly doing what it should be doing, and in effect, override that gene that was defective to begin with or give the instructions that were missing that your body needs to function properly. For other diseases, the treatment may entail silencing a gene that is overactive and causing harm. And this is exactly the act of flicking a switch stuck in the “on” position.

Since each person’s genetic blueprint is unique, a fully customized gene therapy often requires a little tweaking. The specific corrected gene, the vector used to deliver it, or the way the therapy is given might need to be tailored to a particular patient, for instance. There may be some connection between a patient’s age and the stage of their disease and the kinds of health issues they have, and how the therapy is developed and delivered. But it’s a complicated process that involves a lot of experts, such as geneticists, doctors, and researchers, working together to prepare the best, safest treatment they can for that one person.