Durham, N.C. — At 6 months old John Klor’s parents knew he wasn’t developing normally. He was soon diagnosed with a form of cerebral palsy.

“It was devastating at first. Is he going to be able to walk? Is he going to be able to talk? Is he going to even be able to crawl?” his mother, Melissa Klor, said.

Then, a neurologist suggested an MRI brain scan be done. Blood samples were also taken and sent to a lab at Duke University Hospital.

Doctors at Duke saw signs of a metabolic disorder, not cerebral palsy.

Duke pediatrician Dr. Dwight Koeberl says tests showed John lacked a specific enzyme in his blood. His condition is known as guanidinoacetate methyltransferase deficiency, also called GAMT deficiency.

“The enzyme that's missing is very important for the storage and utilization of cellular energy in muscle and the brain,” Koeberl said.

Doctors say there are only about 40 people worldwide who have GAMT Deficiency.

Duke has one of the few biochemical genetic labs to test for such a rare disorder, and physicians said they hope to develop a test that would work in newborn screening.

The deficiency is treated by restricting the child’s diet. Every day, Melissa Klor mixes a special baby formula with supplements and the amino acids for John.

Now 20 months old, John is doing much better.

Wes Klor said his son went from “zero to a 100 miles per hour in a couple of weeks.”

John will be on the special diet the rest of his life, but with it, his future is bright.