Spinal muscular atrophy (SMA): What you need to know
Spinal muscular atrophy (SMA) is a genetic condition that affects the nerves in the spine. On this page, you will learn how doctors diagnose SMA.
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Patient EducationJul | 17 | 2019
If you have questions or are worried about anything, call the Neurogenetics Unit at 617-726-5732. You can also reach the genetic counselor at 617-726-4878.
Spinal muscular atrophy (SMA) is a rare genetic disorder in which the nerves in the spinal cord slowly become weaker or stop working. This can affect your child’s ability to crawl, walk, eat or breathe.
SMA is caused by a mutation (change) in the SMN1 gene (piece of genetic material). The change causes lower levels of survival motor neuron protein (a protein that helps certain nerves and muscles work properly). Without this protein, nerves in the spine do not work as they should.
A child can inherit SMA in an autosomal recessive manner. This means that he receives 2 copies (one from each parents) of the non-working SMN1 gene to have SMA.
There are four different types of SMA:
Rev. 3/2018. Reviewed by the MGHfC Family Advisory Council. This webpage is intended to provide health information so that you can be better informed. It is not a substitute for medical advice and should not be used to treatment of any medical conditions.
Spinal muscular atrophy (SMA) is a genetic condition that affects the nerves in the spine. On this page, you will learn how doctors diagnose SMA.
Spinal muscular atrophy (SMA) is a genetic condition that affects the nerves in the spine. On this page, you will learn about the symptoms of SMA.