Gene Therapy For Inherited Disease In The Unborn Child

Forbes

2 days ago

Until recently, even the most advanced gene therapies could only be given after a child was ... More born—often racing against time to prevent irreversible damage.
In the first part of this series, we explored how early genetic screening and gene therapy transform the lives of newborns and their families. Now, we're taking an even earlier step: treating inherited diseases in the womb before birth. Until recently, even the most advanced gene therapies could only be given after a child was born—often racing against time to prevent irreversible damage. But what if we could intervene even earlier?
That's the question now being answered, with some astonishing results. A recent study published in Science Translational Medicine showed that delivering a special kind of genetic therapy directly to the fetus could prevent the onset of spinal muscular atrophy in animal models. Treating the condition before birth may be possible to preserve healthy motor function and prevent the nerve damage that usually begins in the womb. This is the first time we see molecular therapies targeting the root cause of inherited disease before birth.
Another special investigational case, the first in humans, found that providing the mother with gene therapy while pregnant and continuing treatment after birth also prevented the devastating muscle weakness that usually comes with the disease. This is a true leap forward: instead of managing symptoms; we may soon be able to stop some inherited diseases before they ever begin.
The journey starts with advanced prenatal genetic screening. Genetic changes in the developing fetus can be found using a simple blood sample from the mother. When a risk is found, therapy is delivered directly to the fetus, often by injecting medicine into the amniotic fluid. In the case of spinal muscular atrophy, this approach in animal models led to healthier development and longer survival. These findings suggest that intervening before birth can prevent or significantly reduce the neurological damage that begins in the womb and progresses rapidly after birth.
While most of this research has been in animals, the first human steps have already begun. In February 2025, the University of California, San Francisco, reported the world's first attempt to treat a genetic disease in a human fetus using a medication called risdiplam. After learning that her unborn child was at risk, a mother began taking the medication late in pregnancy. The baby was born healthy and—now more than two years old—shows no signs of the disease, though some developmental challenges remain.
Another important step was taken in a clinical trial at UCSF, where doctors successfully treated a fetus with a different rare disease using enzyme replacement therapy, showing that the technology for delivering medicine to the unborn is already here.
Many inherited diseases cause the most significant harm before a baby is even born. By intervening early, we have the chance to save lives and give children the best possible start—preserving their ability to move, think, and grow. This isn't just a medical advance. It's a new way of thinking about what's possible for families facing genetic disease.
Of course, there are still challenges ahead. Many are working to ensure these therapies are safe, effective, and accessible to all who need them. Ethical questions about when and how to use these powerful tools will also need careful thought. The first human applications of gene therapy before birth are expected within the next decade, pending rigorous safety and ethical evaluations. This new era also brings new questions. If we correct a genetic error in a child before birth, will that change be passed on to future generations?
For now, most therapies target the body's somatic cells, not the germline, so the changes are not inherited. However, the line between somatic and germline interventions may blur as technology evolves, raising complex ethical considerations.
The first human trials of in-utero gene therapy are just beginning, and more research is needed. But the direction is clear: as technology advances, we are moving from treating inherited diseases after birth to preventing them at the start of life.
As I have often said, the future of medicine is being rewritten, one gene at a time. This latest breakthrough brings us one step closer to a world where prevention, rather than treatment, becomes the standard for genetic disease, where every child can live their healthiest life from the very start. As discussed in my book, the hope is that every child will soon have the chance to live their healthiest life from the beginning.