What is SMA?
Spinal Muscular Atrophy (SMA) is the term for a group of inherited
neuromuscular diseases affecting thousands of children and adults
all over the world. The disease destroys motor neurons (also called
anterior horn cells) of the spinal cord and brain stem. These nerve
cells deliver electrical and chemical signals to voluntary muscles,
which are used for crawling, walking, head and neck control, swallowing,
and even breathing.
Involuntary muscles, hearing, vision, and intelligence are not
affected. It has been noted that most children with SMA are very
bright, interactive and socially gifted.
IT IS THE NUMBER ONE GENETIC KILLER OF CHILDREN UNDER THE AGE OF
1 of 40 people are carriers of the SMA gene
1 in every 6,000 live births is affected
over 25,000 people in the U.S. have SMA
SMA does not discriminate when it comes to sex, age, race
or ethnic background
"Autosomal recessive" types 1-3. Both parents
must pass on the defective gene in order for their child
to inherit the disease
Four Types of SMA:
Type 1 (Werdnig Hoffmann) – Most
Severe Form. The onset is before birth or up to 6 months of age.
The child will never sit
or stand. Respiratory and swallowing problems are their biggest
threat. Quivering of the tongue is often noticed. This clinical
sign is seen in virtually no other disease in children except for
SMA. The survival rate is usually less than 2 years. However, each
child is affected differently and a small number of children with
Type 1 may survive into their teens or early adulthood. Also, as
more is learned about SMA, the lifespan of a Type 1 child can be
lengthened depending on the severity of the symptoms for each particular
Type 2 - Usually strikes between 9 and 18 months of age. The
child can usually sit independently, however, they almost never
achieve the ability to walk or stand without support. Depending
on severity, many live into adulthood.
Type 3 (Kugelberg-Welander Disease) - Can strike at any time
after 18 months of age. Many children can appear normal until 10
or even older. The degree of weakness varies. They are able to
walk and have normal life spans.
Type 4 (Adult) – There are many
forms of adult onset, differing in age of onset. The degree of
weakness varies greatly with each
Please note: Although the preceding classifications of SMA is useful
to patient and families, it must be noted that these statistics
are not hard-fast rules. The line between each Type of SMA is not
clearly defined and there can be an overlapping of types. Additional
understanding of the gene defects will undoubtedly explain the
tremendous clinical variation that is demonstrated.
Disclaimer: All information contained in this web site is intended
for informational purposes only and is not intended to replace
and should not be interpreted or relied upon as professional advise.
It is strongly recommended that you consult a physician to assess
individual conditions and needs.