Get to Know Gene
Replacement Therapy

Gene therapies have been developed, studied, and clinically researched for over 30 years. They are unique in that they aim to treat diseases using genetic material.1-3

Some gene therapy approaches seek to silence an abnormal gene; others manipulate the mutated gene to function correctly, or, as with gene replacement therapy (GRT), introduce a replacement gene for a missing or nonfunctional one.2,3

New Possibilities for Monogenic Diseases

Although the logic behind GRT is simple, the science behind it has remained elusive for years. Researchers have been pursuing effective ways to correct or replace the faulty or missing genes that cause monogenic diseases. GRT is a favorable approach because it can be used to deliver a functional copy of the damaged gene into target cells, replacing the nonfunctioning gene and restoring gene expression.1-4

Monogenic diseases, including cystic fibrosis (CF), Duchenne muscular dystrophy (DMD), hemophilia, spinal muscular atrophy (SMA), Rett syndrome, and some forms of amyotrophic lateral sclerosis (ALS) and Parkinson’s disease, are ideal targets for GRT because they can result from the loss or malfunction of a single gene.2,4-7

Early initiation of GRT may potentially further prevent disease progression.2,8,9

Discover the Genetic Evolution

The field of genetics has advanced significantly from Mendel's early discoveries. With emerging gene therapy approvals and others currently being developed, a new era of genetic science has emerged.1,4,10,11

The Father of Genetics

Gregor Mendel's pea plant studies help to establish the rules of genetic inheritance.12

The Structure of DNA

James Watson, Francis Crick, and Maurice Wilkins characterize the structure of DNA. They were awarded the Nobel Prize in Physiology or Medicine in 1962 for their discovery.10,13

Gene Therapy Theorized

Gene therapy is first suggested as a treatment for genetic disease in the journal Science.14

The Human Genome Project

Starting in 1984, scientists begin a 15-year odyssey that culminates in successfully sequencing the human genome in the new millennium.15

In the Clinic

A 4-year-old child with immunodeficiency is the first person to undergo experimental gene therapy in the US.16

Challenges and Lessons Learned

A number of individual gene therapy cases result in complications, and a death in a clinical trial sets back research.11

First in the World

China approves the first gene therapy in the world, with an indication for head and neck cancer.17

Ultra-Rare Applications

The first gene therapy is approved by the European Medicines Agency to treat an ultra-rare blood disorder.18

FDA Approval

FDA approves the first gene therapy in the US which is used to treat acute lymphoblastic leukemia. By the end of 2017, the FDA approves another gene therapy for an inherited form of vision loss.19,20

The Age of Gene Therapy

Despite past setbacks, numerous gene therapy approaches are showing promise with viable candidates; clinical studies continue to be conducted in a breadth of devastating genetic diseases. A Science publication declares "Gene Therapy Comes of Age."1