Is SMA a neurodegenerative disease?
Is SMA a neurodegenerative disease?
Spinal muscular atrophy (SMA) is an autosomal recessive neurodegenerative disease and one of the most common genetic causes of infant death. The loss or mutation of the SMN1 gene results in reduced SMN protein level leading to motor neuron death and progressive muscle atrophy.
What is the genetic code of someone with SMA?
What are the genetic causes of SMA? 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). In 94% of all SMA cases, this mutation involves a deletion in a segment known as exon 7.
Does SMA affect immune system?
Surprising new research has found that spinal muscular atrophy, traditionally thought of as a neuromuscular disease, may also affect the immune system. SMA is the number one genetic cause of death in infants, and is caused by the lack of a protein called SMN.
What is SMA mutation?
People with SMA are either missing part of the SMN1 gene or have a changed (mutated) gene. A healthy SMN1 gene produces SMN protein. Motor neurons need this protein to survive and function properly. People with SMA don’t make enough SMN protein, and so the motor neurons shrink and die.
Can SMA be prevented?
No, SMA cannot be prevented and there is no cure.
Who is at risk for SMA?
A carrier is a person who inherits one healthy copy and one faulty copy of the SMN1 gene. About 1 in 40 to 1 in 60 people are carriers of SMA. If both parents are carriers, they have a 1-in-4 chance of having a child with SMA. About 1 in 6,000 to 1 in 10,000 children are born with SMA.
How is spinal muscular atrophy diagnosed?
How is SMA diagnosed? A blood test is available to look for deletions or mutations of the SMN1 gene. This test identifies at least 95 percent of SMA Types I, II, and III and may also reveal if a person is a carrier of a defective gene that could be passed on to children.
Who is at risk of SMA?
One in every 6,000 babies is born with SMA. It is one of the most prevalent genetic disorders affecting young children and a major cause of death in infancy. SMA can strike children at any age.
What part of the body does spinal muscular atrophy affect?
Spinal muscular atrophy (SMA) is a group of hereditary diseases that progressively destroys motor neurons—nerve cells in the brain stem and spinal cord that control essential skeletal muscle activity such as speaking, walking, breathing, and swallowing, leading to muscle weakness and atrophy.
What are the signs and symptoms of SMA?
The severity of the symptoms, the age at which symptoms, begin, and genetic cause varies by type. Many types of SMA mainly affect the muscles involved in walking, sitting, arm movement, and head control. Breathing and swallowing may also become difficult as the disease progresses in many types of SMA.
Which is the leading cause of death in SMA type 1?
Respiratory care. The respiratory system is the most common system to be affected and the complications are the leading cause of death in SMA types 0/1 and 2. SMA type 3 can have similar respiratory problems, but it is more rare.
How is gene therapy used to treat SMA?
Gene therapy in SMA aims at restoring the SMN1 gene function through inserting specially crafted nucleotide sequence (a SMN1 transgene) into the cell nucleus using a viral vector; scAAV-9 and scAAV-10 are the primary viral vectors under investigation.
What kind of tests are used to diagnose SMAs?
The diagnosis is often made after other causes of symptoms have been ruled out.  Tests that may be needed to evaluate a person with symptoms of SMAS include abdominal X-rays , upper GI series, ultrasound, arteriography, and computed tomography (CT scan).