What is SMN SMA?

Spinal muscular atrophy (SMA) types 1 through 4 all result from a single known cause — a deficiency of a protein called SMN, which stands for “survival of motor neuron.” Deficiency of SMN protein occurs when a mutation (flaw) is present in both copies of the SMN1 gene — one on each chromosome 5.

Is SMA neurodegenerative?

Spinal muscular atrophy (SMA) is an autosomal recessively inherited neurodegenerative disease characterized by motor neuron cell loss and muscle weakness and atrophy. SMA is the most frequent monogenic cause of infant mortality.

What is spinal muscular atrophy SMA )? What is it caused by?

Spinal muscular atrophy is a genetic disorder characterized by weakness and wasting (atrophy ) in muscles used for movement (skeletal muscles). It is caused by a loss of specialized nerve cells, called motor neurons that control muscle movement.

What is SMA treatment?

In December 2016, the FDA approved nusinersen (Spinraza), the first drug approved to treat children (including newborns) and adults with SMA. Nusinersen is an antisense oligonucleotide (ASO) designed to treat SMA caused by mutations in chromosome 5q that lead to SMN protein deficiency.

Is SMA painful?

Overall, pain in this population of SMA patients appears to be comparable to that of people with osteoarthritis or chronic low back pain. Despite SMA patients being generally protected from severe pain, younger SMA patients do experience pain at heightened rates.

How is SMA caused?

Most kinds of SMA are caused by a problem with a gene called the SMN1 gene. The gene does not make enough of a protein needed for the motor neurons to work normally. The motor neurons break down and can’t send signals to the muscles. A child with SMA gets one copy of the SMN1 gene from each parent.

Can SMA cure?

As yet, there is no complete cure for SMA. However, the discovery of the genetic cause of SMA has led to the development of several treatment options that affect the genes involved in SMA — a gene replacement therapy called Zolgensma, and two drugs, called nusinersen (Spinraza) and risdiplam (Evyrsdi).