
The baby saved from a rare disease by a first-ever personalized gene fix has reached a big milestone, taking his first steps ahead of Christmas.
KJ Muldoon is walking and getting ready to celebrate the holiday season at home with his parents and three siblings.
KJ was born last year with a genetic disorder called carbamoyl-phosphate synthetase 1 deficiency. Also known as CPS1 deficiency, the metabolic condition affects only 1 in 1.3 million babies and often leads to life-threatening outcomes.
When he was 6 months old, doctors began giving KJ a groundbreaking new treatment -- a personalized CRISPR gene editing therapy at Children's Hospital of Philadelphia.
Doctors save baby's life with first-ever gene fix for deadly rare disease
The gene-editing therapy works like a "molecular spell-checker,” finding and fixing the specific genetic error causing his condition.
After three infusions and after spending the first 10 months of his life in a hospital, KJ was discharged and sent home in June.
Baby saved by gene-editing therapy 'graduates' from hospital, goes home
Since then, KJ has continued to grow and thrive with his family, celebrating his first birthday at home and taking part in one of the family’s favorite rituals -- cheering for their beloved Philadelphia Eagles.
Doctors hope new technology like CRISPR gene-editing therapies can be the key to treating more than 7,000 rare diseases, such as sickle cell disease, cystic fibrosis, Huntington’s disease and muscular dystrophy, that affect approximately 30 million people across the country.
LATEST POSTS
- 1
Midlife weight gain can start long before menopause – but you can take steps early on to help your body weather the hormonal shift - 2
Blue Origin’s New Glenn rocket landed its booster on a barge at sea – an achievement that will broaden the commercial spaceflight market - 3
Interstellar comet 3I/ATLAS reveals weird wobbling jets in rare sun-facing tail - 4
Nestlé recalls infant formula in 49 countries. See list. - 5
New York to require social media platforms to display mental health warnings
Baidu robotaxi outage in Wuhan caused by 'system failure', police say
New science points to 4 distinct types of autism
The Electric Toyota Hilux Is Finally here, But It's Not Cheap
Before Cheap Cars Were Common, This Fiat Changed Everyday Life for Millions
The wolf supermoon will kick off 2026 with a celestial bang. Here's when and how to see it.
From Overpowered to Coordinated: Individual Accounts of Cleaning up
US FDA investigates Takeda's blood disorder drug after pediatric death
Europe’s EV Boom Was Real in 2025. The Real Fight Starts In 2026
China and Pakistan issue five-point peace plan for Middle East













