Solving a rare disease puzzle is hard. There are now nearly 8,000 rare diseases, and many of those have patient numbers in the single or double digits worldwide. Most doctors have never even heard of these conditions, and the gene mutations responsible for their underlying cause can take months or even years to make their way into commercially available genetic tests. This leads to more diagnostic delays for patients and frustration for families hoping to build their patient communities.
To create awareness for MEPAN so that no patient goes undiagnosed, it’s important that genetic testing labs that screen for these types of conditions know about new gene mutations that cause disease. In MEPAN the MECR gene that helps the mitochondria make fatty acids doesn’t work properly, ultimately affecting areas of the brain that govern voluntary movement and speech. Eventually the retina can be damaged as well, resulting in vision loss. Many labs don’t include MECR in tests that would help diagnose these patients, who present with a movement disorder or spasticity that can often be misdiagnosed as cerebral palsy.
So we began an outreach campaign in September 2019 to contact major genetic testing labs In the U.S. and Europe to share information about the condition and ask them to include MECR in genetic panels that can diagnose movement disorders or mitochondrial or ocular diseases. The more labs that have MECR in these tests, the faster patients can get a diagnosis and receive interventions that might help, like lipoic acid or dichloroacetate. Typically, the earlier a rare disease patient can receive a possible treatment, the better the outcome.
Many companies we contacted were sympathetic to our situation, and some agreed to add MECR to additional genetic tests. Others said that would at least consider our request (it’s a complicated process and there are costs involved) and add MECR to their list of future updates. VariantYX posted a blog about MEPAN and how their process works for updating genetic tests, and Lineagen added Carson and Chase’s story to a family genetic testing website they maintain.
What I learned is that there are no standardized processes for adding genes to genetic tests, and that each lab has different criteria and timelines for updating them. There are hundreds of new disease-causing genes being discovered every year, but it can be years before they are added to genetic tests that can help diagnose the genetic conditions they are associated with. Even worse, there are no standards for revisiting genetic test results that were previously inconclusive to see if the latest research has uncovered new findings that may help. This must change.
We’re doing our part to move the research forward – every little bit helps.