What is Spinal Muscular Atrophy?
Written by Katie Poole
Not many people know what Spinal Muscle Atrophy is. Basically, Aubrey's body is failing her because her motor neurons are not getting enough protein from her body to stay vibrant and alive. They (motor neurons) eventually die since they cannot function. What this means is that Aubrey will never sit up or walk and will have many issues with her respiratory system. Most children with SMA type 1 loose their ability to swallow. Aubrey has had a feeding tube inserted, but is still currently taking her food by mouth. The protein that our bodies get come from a gene called SMN1, she unfortunately does not have this gene. The way kids get this disease is by inheriting it from their parents. We are both carriers of a recessive form of the SMN1 gene and have both passed it on to Aubrey. 1 in 40 adults carry this recessive form and parents who are both carriers have a 25% chance of passing it on to a child where they do not have the SMN1 gene.
There are different levels of this disease, type 1, 2, 3, and 4. They are basically broke down based upon how many copies of the gene SMN2 that the child has. SMA type 1 kids have 0-2 copies of the SMN2 gene (Aubrey has 2 which is good for a type 1 child). Basically, the more copies you have the better off these kids are. The reason for that is the SMN2 gene does produce some of the protein the motor neurons need (about 10%). However, the protein produced is considerably less even though SMN2 genes have the capability to produce more.
Aubrey will have a tough road ahead of her. The biggest obstacle that she'll face is her respiratory system. She doesn't have the strength in her muscles to expand her chest cavity sufficiently to use her lungs properly. She is what they call a stomach breather or diaphram breather. If she gets sick with a cold/flu/pneumonia it can be devastating to her body. That is how most of these kids die. It will be very important that we keep her away from illnesses throughout the winter. If anyone is sick or has a sick child we will need to stay away from you. If you know you are sick or have been around someone who is sick please do your best to stay away from us for that time period.
OK, now for some good news. We are in the right city for this type of disease. The UW Childrens Hospital has one of the top doctors in the nation for fighting this disease so we're very happy about that. We've met with this doctor (Dr. Mary Shroth) numerous times and she is wonderful. The treatment for this has come a long, long way in the last 10 or so years. She has gotten us a few machines that we use on Aubrey to help her day to day life. The old information regarding this disease was that the child would have a 50% chance of living past the age of 2 and that most would die before the age of 3. That is no longer the case for the kids that are in the hands of the right doctors. Many of these kids are living well past those ages. I can't tell you the relief we had after our first meeting with Dr. Shroth. We went in thinking that this was a death sentence and she was able to give us hope for something better.
We are very thankful for what we have and really are approaching this head on with a positive attitude. Aubrey is a fighter, you can see it in her. We truly believe that this journey will take us towards something wonderful. There are many promising things happening in the medical community dealing with this type of disease. Not only the drugs I spoke about earlier, but Stem cell research has a lot to do with that as well. The Stem cell research is still in very early stages, but the results from the testing on animals is quite amazing. Human testing is still a few years away though. They really are just beginning to understand how to combat this type of disease.
SMA Facts Spinal Muscular Atrophy (SMA) is a genetic and often fatal disease that destroys the nerves controlling voluntary muscle movement, which affects crawling, walking, head and neck control and even swallowing SMA is the number one genetic killer of children under the age of two
1 in 40 people carry the gene that causes SMA
SMA effects all ages, races and genders
SMA is classified into four types based on milestones achieved at the onset of SMA
The patient with type III can stand alone and walk, but may show difficulty with walking at some point. Also, with type III, a fine tremor can be seen in the outstretched fingers.
There is no cure or treatment for SMA, but research provides hope.
What causes SMA?
Spinal Muscular Atrophy is an autosomal recessive disease. In order for a child to be affected by SMA, both parents must be carriers of the defective gene, and both must pass this gene on to their child. When both parents are carriers, the likelihood of passing this gene along to a child and having an affected child is 25%, or 1 in 4. In each pregnancy, there is also a 50% chance the child will be a carrier and a 25% the child will be completely unaffected.