Since he was born, Harrison Snow has suffered from an undiagnosed muscular disease that led to difficulties speaking, swallowing and breathing. He spent nearly every day in a state of fatigue and exhaustion. After four years of searching for a diagnosis, his family contacted the Rare Genomics Institute. The patient advocacy team worked with the Snow family to partner with two other institutions, the Scripps Institute and the Mayo Clinic.

Finding a diagnosis

Harrison underwent exome sequencing at the Scripps Institute. The sequencing led to a diagnosis of a neuromuscular disease called congenital myasthenic syndrome (CMS), a very rare disease affecting around 1 in 500,000 people. CMS has 12 subtypes, and the sequencing was also able to pinpoint the exact subtype of the disease that Harrison was diagnosed with. Harrison was diagnosed with one of the rarest cases of CMS, with only 12 reported cases in the entire world.

In April 2015, the family was able to see the leading specialist in CMS at the Mayo Clinic, who had actually discovered several subtypes of the disease. The family learned that there are currently five drugs available to treat the symptoms of CMS. Certain medications that are greatly effective for one subtype can harm patients with other subtypes, so knowing Harrison’s specific genetic makeup allowed the doctor to prescribe an effective course of treatment.

Knowing the next steps

Harrison started taking albuterol syrup, and the family has already seen a remarkable improvement in his condition. “He has a ton of energy…we can hardly make him sit down to watch a TV show these days!” says Susan, Harrison’s mother. “He is talking much better, he is swallowing without issue, his breathing is slower and deeper. We have been so encouraged by the changes.”

“This entire experience has honestly been life-changing for us,” Susan continues. “Instead of lying in bed at night wondering what our son has and if he’s going to worsen over time, we now know that his disease is not degenerative and that he will likely live a long life. While he will always have medical challenges, this diagnosis has given us a course of treatment to help to alleviate his symptoms. We are now on the radar of the nation’s specialist in this disease, so if any new courses of treatment arise, we could have access to those treatments through him. We can now make plans for our family’s future… something we never felt comfortable doing without a diagnosis.”