But soon, the doctors' reassurances disappeared.

"They told us she would never walk to kindergarten and that she would die by the time she was 13," remembers Brittany's mother, Venna Carr.

Brittany has been diagnosed with spinal muscular atrophy, a genetic disease which causes children to have difficulty controlling muscles for crawling, walking, swallowing, breathing and moving the head and neck. The motor neurons for these muscles degenerate, causing the muscles to atrophy to the point where a child becomes unable to swallow and breathe.

'[Brittany] can't run, she can't jump, she can't keep up with other girls when they go to the mall,' — Venna Carr, Brittany's mother

Until recently, SMA was thought to be incurable. But a flurry of new scientific breakthroughs is offering unprecedented hope of a potential treatment.

The Search for a Cure

The first major advance came in 1995, when researchers pinpointed the cause of SMA in a defective gene that makes a person unable to produce the survival motor neuron protein , a key substance in maintaining nerves for muscle movement.

Then, earlier this month scientists at the University of Bonn in Germany announced they had discovered how to stimulate production of the missing protein in animals with the disease.

If this research can be translated to humans, a simple treatment could prevent symptoms of the disease, the researchers wrote in the Aug. 15 issue of the Proceedings of the National Academy of Sciences, where they presented their findings.

"Breakthroughs like [this] give hope to all the families living with this devastating disease," said Audrey Lewis, president of Families of SMA, reacting to the announcement.

Families of SMA has lobbied for increased research on the disease, which affects one in 6,000 children and is the leading genetic killer of children under the age of 2. SMA is common for a genetic disease, many of which strike only around 1 in 50,000. The organization has even launched a partnership for-profit genetics company, Aurora Biosciences, to aid in the search for a SMA treatment.

Aurora Biosciences is using its technology to screen hundreds of thousands of potential compounds for their ability to stimulate production of the deficient protein.

Families of SMA members hope this private effort, together with the work of the University of Bonn and other academic groups, will produce an effective treatment in the next five to 10 years.

But for families who struggle with this disease day in and day out, that's a long time.

The Hurdles of SMA

The most acute form of SMA — Type I — leads to respiratory failure and death in infancy or childhood. Chronic Type II SMA prevents suffers from walking and can lead to respiratory failure beginning at age 3 through adulthood. Those who have Type III, a milder form of the disease, can walk but have difficulty getting up on their own and suffer from slower muscle degeneration.

The financial burden of SMA is also heavy. Some of the necessary medical equipment is covered by insurance. But many items — wheelchair lifts, house ramps, special toilet seats and lifetime physical therapy — are not paid for by many plans, noted Cindy Schaefer of Cary, N.C., whose six-year-old son Kevin suffers from Type II chronic SMA.

The issue of how to pay all the bills used to greatly upset the Schaefers. But now the couple tries to focus on the present, to enjoy their son as the vivacious, outspoken six-year-old he is today, before his body catches up with him.

"The most painful part is, it's a physical disease, not a mental disability," said Chris Spancake of Thousand Oaks, Calif., who lost his 2-year-old son Brian to acute SMA nearly three years ago. "These children are extremely bright but are limited."

Brittany, who has outlived her initial prognosis, is now 15. She still attends regular school and gets around without a wheelchair, yet the disorder has robbed her of many childhood pleasures.

"She can't run, she can't jump, she can't keep up with other girls when they go to the mall," said Venna. "Her dream is to rollerblade but she just wishes she could go upstairs."

Despite her difficulties, Brittany knows it could be worse. "She wants a cure because of the other children dying every day," Carr said.

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