GRAND PRAIRIE -- Chrissy Grube will never run and play with her first-grade classmates. If the 6-year-old is lucky, the day will come when she no longer needs a wheelchair.
If she's not, her rare genetic disorder could prove fatal by early adulthood.
Giant axonal neuropathy -- so uncommon that only 10 people in the U.S. are known to have it -- slowly robs her of control over her body. She gets winded easily, is prone to choking and sometimes suddenly loses the ability to stand.
Making matters worse for her family, Chrissy's baby sister, Amanda, may have inherited the same defective gene pair. After months of waiting for laboratory results from overseas, word came last week that the testing process will have to begin anew.
It's a heartbreaking story that has put her parents through an exhausting emotional wringer. But if you're looking for a pity party, you won't find it at Chrissy's house.
Her mother, Katherine Grube, a Spanish teacher at Arlington Bowie High School, relies on prayer to get her through the difficult moments and on an extended support group to maintain a world in which Chrissy sees herself as special no matter where she goes.
"We are all people of very, very convicted faith," Grube said as her daughters played cheerfully at home. "The future is in God's hands, and that's enough for us."
Plenty of support
Chrissy's disorder is so rare that no official statistics exist on its incidence, said Steven Gray, a researcher at the Gene Therapy Center at the University of North Carolina at Chapel Hill.
The nonprofit Hannah's Hope Fund has identified fewer than 50 people worldwide with the disorder, although there are almost certainly more, Gray said. Chrissy is the only known Texas patient.
The symptoms and prognosis are similar to those of Lou Gehrig's disease, except GAN emerges in children. In layman's terms, Gray said, the communication between the brain and nerves that fire muscles becomes clouded.
"It's like the old land line phones," he said. "You can call somebody in your town. But there's something wrong with the line that runs to the next town, so when you try to call, sometimes you can get through and sometimes you can't."
The disorder is challenging for patients and their caretakers, but Chrissy has an enormous support network.
It includes the staff and students at Starrett Elementary School, where classmates take turns pushing her wheelchair and help keep an eye on her.
"They are very protective of her," Principal John Wofford said.
It also includes the congregation of First Baptist Church of Euless, which the family attends, and a strong nucleus of close relatives.
Asked about her day at school, Chrissy flashes a little smile but doesn't say much. Her red-rimmed glasses give her a studious look that Wofford said reflects her classroom demeanor.
"If it's not about math or PE, we don't hear about it," Grube said, gazing at her daughter. "Or boys."
A visitor asks Chrissy if she has a boyfriend. "She has lots of them," Grube says, prompting Chrissy to exclaim: "Mom, we've gone over this!"
"We're choosing to enjoy every minute we have with Chrissy," Grube says. "We're just thanking God she's so surrounded by people who love her and are willing to fight for her."
Search for a cure
Gray, who has led the 4-year-old U.S. effort to find a cure for GAN, believes that researchers may be close to a breakthrough. He hopes to win approval from the Food and Drug Administration to use a version of AAV, a human virus not known to cause disease, to carry a correct copy of the GAN gene into patients' brains and spinal cords. After being injected into the patient, the virus would work as a "delivery truck" to transport the gene to the right location, Gray said.
The treatment has shown promise in laboratory tests using patients' skin cells, Gray said. But the first phase of a clinical trial is, at best, a year away, he said.
"We have multiple lines of evidence that this can help the underlying causes of GAN," he said. "But we won't know for sure how well this will work in humans until we try it."
Partially because the disease is so rare, little government funding has been awarded for the research.
The money from Hannah's Hope, a New York-based organization founded by the parents of Hannah Sames, who was diagnosed in 2008 when she was 4, has helped research progress much faster than it would have otherwise, Gray said.
Watching the group's tireless work has turned his own effort into something more than just a science project. He has come to know some of the families dealing with the disorder. His daughter has even played with some of the patients.
"Every day I think, 'What if that was my kid?'" he said by phone. "That's a pretty strong motivator. This has become personal for me. I want to help those families."
Besides donating money to www.fightforchrissy.com to continue the research, Grube says, people can help by praying.
"Will the treatment work?" she says. "The whole situation is just a big roll of the dice."
Patrick M. Walker,