In a landmark moment for genetic medicine, researchers have successfully used mRNA technology and CRISPR-based (Clustered Regularly Interspaced Short Palindromic Repeats) gene editing to develop a life-saving treatment for a newborn diagnosed with a rare and deadly metabolic disorder. The condition, known as carbamoyl-phosphate synthetase 1 deficiency, disrupts the body’s ability to eliminate ammonia from the bloodstream. Left untreated, it can cause irreversible brain damage or death within the first months of life. Affecting roughly 1 in 1.3 million people, the disorder is among the most severe of its kind.
What makes this medical breakthrough extraordinary is the speed and precision with which it was developed. In just six months, a team at the Children’s Hospital of Philadelphia designed a therapy specifically for one patient. Using mRNA to deliver custom genetic instructions, and CRISPR to perform targeted base editing, doctors corrected the specific mutation causing the disease without the need for traditional gene replacement or a liver transplant.
The therapy uses lipid nanoparticles to deliver the modified genetic instructions into the liver, where the faulty gene’s function can be restored at the molecular level. Messenger RNA (mRNA), a critical intermediary between DNA and the body’s protein-building machinery, played a central role. This molecule enabled the cell’s ribosomes to read the corrected instructions and begin producing the proteins the baby’s body was unable to make on its own.
Unlike one-size-fits-all approaches, this method can be adapted quickly to target other rare mutations. The child received two infusions before reaching nine months old. Weeks later, the infant was able to increase dietary protein intake and cut medication dosage in half without adverse effects. This case marks a turning point in personalized therapy, not only offering hope to those with rare genetic disorders but also setting the stage for a future where treatments are tailored to the individual genome.
Assistant Lecturer at the University of the Basque Country