According to a story from MedicalXpress, it was around 30 years ago when two sons of Marsha and Allen Barnett, named Chuckie and Michael, both passed away from Leigh syndrome. At that time, the disorder had only just been identified and very little was known about it. Now, scientists have discovered the mutation that was responsible for causing the disease in the Barnett family.
About Leigh Syndrome
Leigh syndrome is a type of neurometabolic disease that impacts the central nervous system. Levels of thiamine triphosphate or often abnormally low or absent altogether. Mutations of the mitochondrial and nuclear DNA have been implicated in Leigh syndrome, and there are a number of different variants that have been linked to different genetic abnormalities. Symptoms often appear after a triggering event like surgery or an infection which places strain on the child’s body. Symptoms include vomiting, diarrhea, difficulty swallowing, muscle weakness, dystonia, and ataxia. Treatment is mostly supportive, but may include succinic acid, thiamine, or sodium citrate. A high fat low carn diet can benefit patients with X linked Leigh syndrome. Few patients survive beyond their teen years; respiratory failure is the most common cause of death. To learn more about Leigh syndrome, click here.
Over the years, a number of different mutations have been linked to Leigh syndrome, but in some patients, the mutation that causes the syndrome is not known. This can make diagnosing the disease much more difficult. It is vital that all of the mutations that cause Leigh syndrome are identified. This knowledge has important implications for diagnosis and the development of new treatments.
The newly discovered mutation affects the USMG5 gene, which appears on the nuclear DNA. In order to discover this new mutation, the scientists used data from Chuckie and Michael as well as two other patients whose mutation had not been successfully identified. Mutations of this gene had not been associated with any other human diseases before.
This mutation is considered a “founder” mutation that most likely appeared spontaneously in an Ashkenazi Jewish ancestor of the Barnetts. It probably first emerged hundreds of years ago. This discovery will allow for the development of new therapeutic approaches and will help doctors diagnose Leigh syndrome more quickly.
Check out the original study here.