Loaded for Bear — A Rare Disease Diagnosis

About a year and a half ago we realized that (our now 11 year old daughter) Maya’s “differences” were not normal. When I held Maya’s and her brother’s hands on the way to class, it seemed weird that Maya always seemed to tug and pull on my hand. It was such a contrast to the way her brother held my hand.

After months, we finally had an appointment with a neurologist. The neurologist did a couple of basic tests as part of his examination (finger to nose, hop on one foot, walk across the room heal to toe) and it was very clear that something was very, very wrong. After a year of blood tests, spit tests, Exome sequencing and eventually a trip to Massachusetts General we had a diagnosis: ATYPICAL TPP1 DEFICIENCY or Autosomal Recessive Spinocerebella Ataxia 7 (SCAR 7).

Since Maya is the eighth reported SCAR7 case (in the world) she does not “have a community” and science/medicine are slow to catch up to her reality. We know that Maya’s condition is caused by mutations in the same gene that causes CLN2 (Battens Disease). However, she does not have Battens Disease. Effectively, Maya’s mutations of the TPP1 gene means that she has some residual levels of TPP1 activity and kids with Batten’s have a roughly zero level of TPP1 activity.

In order to find a cure/help for Maya, we need to find more kids and adults with Maya’s exact phenotype/diagnosis. The more we find, the more science, medicine and the respective communities will pay attention and join the fight. Ultimately, our hope is that answers to Maya’s condition will help the Battens community (i.e., determining the necessary therapeutic levels of TPP1 replacement enzymes for kids with Battens) and the Ataxia community (i.e., our path to a SCAR7 diagnosis was lucky… it is likely that there are a number of children and adults with Maya’s symptoms (or the natural progression thereof) who are simply un-diagnosed, but have TPP1 mutations).

If you are out there, then we need to find you.

This is an excerpt from a longer blog entitled “Loaded for Bear — A Rare Disease Diagnosis”