SMA Facts

  • SMA stands for keq-11.jpgSpinal Muscular Atrophy.
  • SMA is the #1 genetic killer of children under the age of 2.
  • SMA is estimated to occur in nearly 1 out of every 6,000 births.
  • SMA is a motor neuron disease that weakens the proximal muscles used for holding your head up, crawling, walking, breathing and eating.
  • The ability to feel, touch, smell and taste are not affected.
  • The brain remains unaffected and children with SMA have been known to be very intelligent and sociable.
  • SMA is a recessive trait, so both parents must pass on the gene for SMA and their chance of having a child with SMA is 25%.
  • There is currently no treatment and no cure, but the National Institutes of Health (NIH) and the National Institute of Neurological Disorders and Stroke (NINDS) selected SMA as the disease closest to treatment of more than 600 neurological disorders.
  • Carrier testing for SMA can be done through a blood sample. In most cases there is no family history and SMA carrier testing is not part of routine pregnancy screening, but it can be requested. It is especially important for family members to get tested if SMA has shown up in their family history.
  • SMA affects all races, ages, and genders.

There are 4 different categories of SMA based on the milestones achieved.

  • Kennady was Type I, which is the most common and most severe form of SMA. This type is also known as Werdnig Hoffmann Disease. Children with this type of SMA are not able to sit up without support.  This type most often gets diagnosed when a child presents with a "floppy" muscle tone and is unable to hold their head up, or sit unassisted.  Type I often gets diagnosed between birth and 6 months old. Children with type I often have issues with their swallow, and are at risk for respiratory illness due to muscle weakness.  The average life expectancy is less than 2 years old.
  • Type II children are often able to sit up, but are not able to walk. Their ability to eat may or may not be affected.  Children with type II often get diagnosed when they do not achieve the developmental milestone of walking, or unexpectantly lose the ability to walk.  They may get diagnosed between 7 and 18 months old.  This type is also at an increased risk for respiratory infections.
  • Type III/IV occurs in adolescence/adulthood and is the least life threatening form of SMA.  Many are able to walk, but weakness causes these patients to eventually use a wheelchair.