Amyotrophic lateral sclerosis (ALS) is a disease that involves the death of neurons that activate voluntary muscles. These muscles are called skeletal striated muscles and are responsible for our ability to walk, talk and even breathe. The disease, also known as Lou Gehrig’s or Charcot disease, is therefore characterized by stiff muscles, muscle twitching and gradually worsening weakness due to muscle wasting. All of these symptoms result in an increased difficulty in walking, speaking, swallowing and, ultimately, breathing.
The cause of ALS in not known in 90% to 95% of cases; the other 5% to 10% of the cases are genetically transmitted from the patient parents, usually as a result of a mutation in the C9orf72 gene. There are ongoing efforts for a efficacious therapeutic response to the disease but, until now, our incomplete knowledge of its processes has proved to be an obstacle.
A recent study published in the journal Nature Neuroscience may help the scientific community a little further to understand the disease. Researchers from the Mayo Clinic’s Florida Campus led by Dr. Petrucelli and Professor Hu Li looked at differences between the genetically transmitted and the usual form of ALS, specifically focusing on abnormalities in the levels and processing of ribonucleic acids (RNA), the molecules used as middle products between gene information and protein synthesis.
Although there are various similarities between the two forms of the disease, these results show there are also many differences between the RNAs altered in sporadic/usual forms compared to C9orf72 mutation-associated cases. These findings might indicate there are different factors contributing to the disease in such patients and that therapeutic targets may also be different.
The success of novel therapies is thus dependent on specific tailoring to particular ALS patients. Importantly, the study has created a great deal of novel data that can accelerate research and prove invaluable not only in therapy research but also for early diagnostic development and determination of prognostic factors.