Ricki Lewis

Last year, nine-month-old KJ Muldoon made history when a variation of CRISPR gene editing, called base editing, swapped one DNA building block for another at a specific part of his mutant gene. He had inherited a urea cycle disorder called carbamoyl-phosphate synthetase 1 (CPS1) deficiency. It hampers the ability to digest protein and is among the rarest of the rare, affecting only about one in 800,000 to one in 1.2 million newborns, in different populations.

 

The boy had inherited one mutation from each parent; they are unaffected carriers. His liver couldn't produce the crucial enzyme CPS1, and as a result, ammonia released from the breakdown of the amino acids in dietary proteins was accumulating in his bloodstream. Organ failure and, ultimately, brain swelling and coma would follow. Half of the babies with the condition do not survive infancy.

 

KJ's case was reported in The New England Journal of Medicine May 15 of last year, "Patient-Specific In Vivo Gene Editing to Treat a Rare Genetic Disease." DNA Science covered it here.

 

More recently, KJ appeared at a news conference March 2, 2026, to celebrate Rare Disease Day. The toddler demonstrated his ability to walk. He has very mild symptoms of the ultrarare disease.

 

 

To continue reading, go to DNA Science, where this post first appeared.

On a spectacular September Sunday in 2008, 8-year-old Corey Haas, using his cane and holding his mother’s hand, stepped tentatively forward on the pathway leading into the Philadelphia zoo. Hearing kids yelling about the giant balloon hanging above the zoo, he looked up – and screamed. It was the first time he’d seen the sun. Corey was headed toward certain blindness when he’d had gene therapy at Children’s Hospital of Philadelphia, just days earlier.

So begins the talk I’ve given many times since publication of my book, "The Forever Fix: Gene Therapy and the Boy Who Saved It.

Last Thursday, I was glued to my laptop, watching and listening to physicians, researchers, family, and patients present their cases for FDA approval of
Luxturna (voretigene neparvovec), the gene therapy that Corey, now a high school senior, received. He and dozens of others participating in several clinical trials can now see, thanks to the gene therapy for RPE65-mediated inherited retinal dystrophy. The treatment introduces functioning genes into the thin layer of pigmented cells that hugs the rods and cones – one time. Read More 

The pharmaceutical industry rightly calls the stage in drug development between basic research and clinical trials the “Valley of Death.” This is when a potential treatment that’s worked in mice, monkeys, and the like catapults to a phase 1 clinical trial to assess safety. It’s rare.

Francis Collins, MD, PhD, director of the National Institutes of Health, calls this period “where projects go to die.” The reason: $.

Matthew Herper writes in Forbes that the cost of developing a new drug is $4-11 billion, not the $1 billion that Pharma often claims. Yet even that $1 billion is unimaginable, especially when you put a face on a rare disease and witness what the family goes through to leap to phase 1.

For me, that face belongs to 8-year-old Hannah Sames, of Rexford, New York. Read More 

In this age of expiring drug patents and stalled pipelines, I was pleasantly surprised to find in my morning batch of news releases four reports of promising, eclectic ways to fight diverse diseases. The  Read More 

Gene therapy is experiencing a renaissance, with many of the recent successes in children. For some conditions, the younger the child, the better the genetic correction, because affected tissues degenerate with time. This is the case for adrenoleukodystrophy (ALD), the “Lorenzo’s Oil” disease that strips the insulation from brain neurons. One goal of  Read More 

I couldn’t help but stare at the ad: the sleek double helix winding behind the coiled container of makeup looked eerily like the covers of my human genetics textbook and upcoming book about gene therapy, both of which have DNA as a backdrop to faces. The standard beige goo that is Revlon’s Age Defying with DNA Advantage™ cream makeup swirls symmetrically upward, resembling more a soft-serve ice cream cone before the indentations are licked away than it does the molecule of life. I decided to investigate. Read More