SMA: DEADLY, COMMON AND UNKNOWN

Though virtually unknown to the general public, Spinal Muscular Atrophy (SMA) is a deadly and relatively common genetic children's disease. It is the leading genetic killer of infants and toddlers, and even in less severe cases, causes tremendous suffering and eventual death. Over 25,000 Americans have the disease. Up to 1,000 new babies - an estimated one in every 6,000 live births - are afflicted with SMA each year. One in 40 people (approximately 7 million Americans) carry the gene that causes SMA.

THE DISEASE

SMA is a genetic, motor neuron disease characterized by the wasting away of skeletal muscles. Caused by progressive degeneration of nerve cells in the spinal cord, the disease leads to increasing muscular weakness and atrophy. SMA is often compared to a genetic form of Polio. Over time, its victims continue to lose muscle control and strength, leading to progressive inability to walk, stand, sit up, and eventually move. Eventually, the weakness causes muscle contractures, bone deformities, and spinal deformities such as severe scoliosis. Death is eventually caused by respiratory and other complications. Very severe cases result in death in the womb or shortly after birth, while less severe cases can take many years to develop. Even in less severe forms, patients generally require ongoing physical therapy, frequent hospitalization, and repeated surgery to help slow down the impact of the disease.

RESEARCH RATIONALE

Researchers at the National Institute of Neurological Disease and Stroke (NINDS) at the National Institutes of Health (NIH) designated SMA as a model disease for a new approach to funding translational research.  Translational research develops findings by scientists in the lab into drugs and treatments that doctors can use to save the lives of patients.  NIH researchers selected SMA as the model for translational research because, compared to most genetic diseases, they believed SMA:

• Has a strong probability of treatment or cure

• Is very severe

• Is relatively common

• Has no current treatment

Development of translational research initiatives is critical to the development of a treatment not only for SMA, but also for other diseases. 

RAISING AWARENESS

Though virtually unknown, the population of people suffering from SMA is similar to those suffering from ALS and Cystic Fibrosis.  The incidence of SMA, an estimated one in every 6,000 live births, is similar to Duchenne Muscular Dystrophy and Tay Sachs Disease (in the Jewish population).

For many years, SMA was poorly understood and difficult to diagnose. However, dramatic discoveries made in the past seven years have catapulted SMA from being a poorly understood disease to one with higher prospects for treatment than perhaps any other major genetic disease.

In severe cases, SMA is often under-diagnosed, since it typically results in fetal or infant death. Even in milder forms, SMA was historically difficult to diagnose. Symptoms and age of disease onset vary tremendously among patients. In fact, until recent advances pinpointed the genetic cause, SMA was believed to be a family of related diseases rather than one disease. Today, those degrees of severity are recognized by the medical community as various forms of SMA, which are distinguished by age of onset and acuteness.