Genetic Disorder Causing Amyotrophy in Extremities and Facial Palsy Newly Identified
A team of Korean researchers are drawing much attention after reporting to the global academia a new genetic disorder that accompanies amyotrophy in lower and upper extremities and bilateral facial palsy.
Prof. Byung-ok Choi of Neurology, SMC, Prof. Jieun Lee at Samsung Advanced Institute for Health Sciences & Technology (SAIHST), Prof. Ki Wha Chung, Kongju National University et al conducted joint research with the support of Korea’s Ministry of Health and Welfare and the National Research Foundation of Korea. In November, the finding were published in the most prestigious journal in clinical neuroscience, the Annals of Neurology. (IF=11.9)
They found a new gene called ADSSL1 which makes no symptom at birth, but in adolescence it causes rimmed vacuoles* in muscle tissues and an increase in creatine kinase blood levels that indicates bilateral facial palsy and muscular disorder in extremities. The disorder becomes severe over time, making the patients unable to walk alone.
*Vacuole: an empty space within a muscle cell that does not have muscle fibers.
The team performed an advanced genomic analysis technique, whole exome sequencing (WES) for two Korean families with the symptoms. This new approach makes it possible to analyze the whole human genome. Through the test, they found out that this was a new genetic disorder where a recessive mutation in ADSSL1 located in the long arm of Chromosome 11 is inherited.
The gene produces muscle-specific adenylosuccinate synthase. The researchers has successfully created a zebrafish model by injecting a mutated human ADSSL1 gene into zebrafish whose genome is similar to human one, and noticed that similar symptoms appeared in the fish. Then, they introduced a normal ADSSL1 gene to the fish and the muscles returned to normal. This way, they proved that ADSSL1 is the cause of the disorder.
This research is well received by the academia as a significant study that identifies an unknown genetic disorder and related genes scientifically. Also, it showed injecting a normal gene may improve the muscle functions, suggesting the possibility of future gene therapy.
Prof. Choi of SMC stressed, “It is expected that the findings of this research will facilitate a deeper understanding of life and give important information about the role of each gene.”