How Does Gene Therapy Work? Correcting Disease-Causing Genetic Variations

02/23/22 • 10 min

Not all genetic variations are associated with threats or harms to human health. Some even protect us, such as genetic variations that have been shown to make bones harder or the heart more impervious to disease. But while some genetic variations are positive, others can cause or contribute to disease.

In this episode, we answer the question of how does gene therapy work, and learn how gene therapy replaces and repairs certain gene variants, and is changing the trajectory of genetic diseases.

For several years, Dr. Jean Bennett at the University of Pennsylvania’s Department of Ophthalmology Center for Advanced Retinal and Ocular Therapeutics investigated the possibility of replacing gene variants in the retina – which cause blindness – with copies of healthy ones.

After successfully treating blind puppies, Dr. Bennett and her colleagues turned their attention to treating human eyesight.

The retina turned out to be a good target site for gene therapy. In most parts of the human body, our cells keep dividing after we’re born. But not the rods and cones in our retina – these photoreceptor cells don’t regenerate.

A major obstacle in the development of gene therapy is the tendency of cloned genes to get lost in the process of cell division before they have a chance to integrate into the host DNA. Because retinal cells don't divide after birth, the cloned gene may be expressed for a prolonged time

In 2017, after decades of painstaking research, building on the efforts of countless scientists throughout history, Dr. Bennett and her colleagues had the evidence that gene therapy may be used to treat genetic conditions in humans.

Since then, gene therapy has undergone giant leaps in the treatment of specific diseases.

And record numbers of gene therapy trials are ongoing, including potential treatments for conditions such as sickle cell disease and Parkinson’s disease.

It’s just one of many ways that the field of gene therapy is poised to change the world in the years to come.

For more education on gene therapy, visit www.genetherapynetwork.com.

In this episode, we answer the question of how does gene therapy work, and learn how gene therapy replaces and repairs certain gene variants, and is changing the trajectory of genetic diseases.

After successfully treating blind puppies, Dr. Bennett and her colleagues turned their attention to treating human eyesight.

Since then, gene therapy has undergone giant leaps in the treatment of specific diseases.

And record numbers of gene therapy trials are ongoing, including potential treatments for conditions such as sickle cell disease and Parkinson’s disease.

It’s just one of many ways that the field of gene therapy is poised to change the world in the years to come.

For more education on gene therapy, visit www.genetherapynetwork.com.

Previous Episode

A Brief History of Gene Therapy and the Discovery of DNA

In this episode, we explore some of the major scientific findings – like discovering DNA – that set the stage for the development of gene therapy and its groundbreaking potential when it comes to the treatment of genetic diseases.

The very idea of gene therapy wouldn’t be imaginable had two pairs of pioneering scientists not bonded decades earlier. In 1951, a young chemist named Rosalind Franklin and her colleague Maurice Wilkins at King’s College in London were using X-ray crystallography to try and perceive the properties of a theoretical molecule known as deoxyribonucleic acid.

At the time, many scientists believed that all the genetic information about living organisms was contained in a molecule called DNA. But no one had figured out exactly what it was, or what it looked like.

After attending a presentation by Franklin, James Watson – who was also studying the topic – connected with Francis Crick. Crick had been studying the concept of base pairs – the idea that nucleic acid is composed of chemical bonds between not one but two sets of molecules, each supporting the other, much like the two sides of a ladder support the rungs in between. Excited by their shared passion, Crick and Watson in Cambridge began to build models of possible DNA structures, trying to figure out just how all the pieces fit.

Eventually, Franklin, Wilkins, Watson and Crick’s efforts joined, and DNA was discovered. Then, in the 1970s, DNA was successfully transferred from one life form to another.

Less than 50 years after Crick, Franklin, Wilkins, and Watson first showed us what this molecule looks like, genetic engineering gave us the ability to reprogram it when it isn’t working.

Scientists and doctors began to dream big: could this technology eventually cure all genetic diseases?

There was still work to be done. But, like a tiny plasmid loaded up with recombinant DNA, we were on our way.

For more education on gene therapy, visit www.genetherapynetwork.com.

Next Episode

The Future of Gene Therapy and Genetic Diseases

Peek into the future of gene therapy and its capacity to treat – maybe eliminate – genetic diseases like cancers and hemophilia. Plus, the potential to reverse the effects of aging.

It’s a future scientists have been working toward for years: How to treat complex health problems with gene therapy. And researchers have been making progress. Diagnoses once thought to be fatal are now being looked at in a new light.

This is a welcome sight for physicians, caregivers, and – most of all – for the patients living with these genetic diseases.

One disease that’s impacting lives worldwide is cancer. Nearly 40% of the world’s population will be diagnosed with it at some stage of life.

Typically, cancer treatment takes three forms: chemotherapy, surgery, or radiation therapy. Targeted drug therapies also exist, which work by identifying and attacking cancer cells individually.

But the treatment that many believe has the most potential is immunotherapy.

Immunotherapy uses a patient’s immune system to target and destroy cancerous tumors. And a specific type of immunotherapy known as Chimeric antigen receptor (or CAR) T-cell therapy has particular promise.

Over the last few years, progress with this new class of gene-based treatment has accelerated.

CAR T-cell Therapy is when a patient's own immune cells – the white blood cells called T cells – are genetically altered to target and attack a specific cancer within the body. These cells are first removed from the patient’s blood. Their genes are then altered to produce proteins called CARs, which allow the T cell to better recognize – and attack – specific cancer cells. When the altered immune cells are reintroduced into the patient's bloodstream, these proteins latch onto both healthy and cancerous cells, destroying the cancerous cells while leaving the healthy cells unharmed.

CAR T-cell Therapy has the ability to revolutionize cancer treatment and prevent relapse, as these cells can potentially continue to attack cancerous cells in a patient’s body for years. But it’s not a solution for everyone. Only about 40% of patients have long-term responses.

But if this therapy achieves what scientists believe it can, chemotherapy could be a thing of the past, and when it comes to the future of gene therapy and genetic diseases, there's reason for optimism.

For more education on gene therapy, visit www.genetherapynetwork.com.