The U.S. Food and Drug Administration today approved Nusinersen, the first drug approved to treat children and adults with spinal muscular atrophy (SMA), a rare and often fatal genetic disease affecting muscle strength and movement. Spinal muscular atrophy is a genetic disorder that affects the control of muscle movement. It is caused by a loss of specialized nerve cells, called motor neurons, in the spinal cord and the part of the brain that is connected to the spinal cord (the brainstem).
The most common form of SMA (types 1-4) is caused by a defect (mutation) in the SMN1 gene on chromosome 5. (People have two SMN1 genes — one on each chromosome 5). A mutation in the SMN1 gene leads to a deficiency of a motor neuron protein called SMN, for the survival of motor neuron. Spinal muscular atrophy (SMA), also called autosomal recessive proximal spinal muscular atrophy and 5q spinal…
