Gene therapy makes a world of difference for young Pratt boy and his family.

Five-year-old Jace Baker of rural Turon smiled his first smile this spring after crying almost non stop for the first four years of his life. On Monday, Jace was still smiling but he made his doctor cry.

Jace, son of Michael Baker and Cassandra Verstraete, was born with a genetic deficiency called Aromatic L Amino Acid Decarboxylase Deficiency (AADC), a very rare, genetically inherited disease.

The disease kept him in constant pain, his mother said, until he had gene therapy surgery in April at UCSF Children’s Hospital in San Francisco.

Monday, Jace traveled with his mother and grandfather Wilson Verstrate to Kansas City for a follow up visit, the first of a series of such visits at six month intervals for the next two years, to check his progress.

“His doctor walked in with tears rolling down his face when he saw Jace,” his mother said. “He’s changed so much that he’s like a ‘new little man’.”

The changes in Jace have been life changing for the family as well, Verstraete said.

“Jace used to cry non stop because of his pain,” she said, “Now he almost never cries. He’s very happy!”

It has been an uphill struggle for the family, both emotionally and financially, during the years before the diagnosis was made and through the surgery. The Pratt community, his mother said, has been there for the family on both fronts.

“I really want to thank everybody who has donated to him and prayed for us,” Verstraete said.

She said about $1,500 was donated through collection jars and other gifts.

Along with his six month follow up appointments, Jace goes to Pratt Regional Medical Center three times a week for physical therapy. Verstraete said she was always optimistic that the gene therapy would make a difference in the life of her son, who is one of only 130 people worldwide who have been diagnosed with the disease that made it difficult for him to function.

The gene therapy surgery is still in the trial stage, according to Verstraete. She said that Jace is the fourth person in the United States to be included in the experimental treatment.

“He’s also the youngest and he received the highest amount, three times the dosage,” Verstraete said.

While in San Francisco, Jace got to meet Gerald Dempsey “Buster” Posey III, catcher for the San Francisco Giants, who gave him an autographed baseball and his own personal baseball bag, which he also autographed.

“It was awesome! Jace loved it!” Verstraete said.

The changes in Jace since the April surgery have been miraculous. Jace now has good head control. He is gaining weight. He has taken an interest in toys and play, his mother said.

“He really is like a new man. Everything about him is different,” she said.

One of the things Verstraete recently learned about her son was the true color of his eyes.

“Before the brain surgery, he could barely open his eyes and everyone thought he had brown eyes. Now, his eyes are wide open and they are beautiful blue eyes,” she said.

Looking toward the future, Verstraete said she has hopes Jace can get a service dog.

In the meantime, Jace has his own Facebook Fan Page, Hope for Jace Lee Baker, where visitors are welcome to follow his progress and cheer him on.