What is ALS?
The only things that are known about Amyotrophic Lateral Sclerosis (ALS), a syndrome which has been around since the time of the Civil War, are its effects on the body. When ALS affects motor neurons, the axon of that neuron, surrounded by Schwann cells of the myelin sheath, begins to collapse. Eventually, the entire motor neuron will degenerate. As the axon breaks down, the waste, neurofilament buildup, accumulates around the nucleus of the cell and causes malfunctioning. The Schwann cells insulate the neurons; as they stop working, control is lost over certain muscles. This loss of control causes eventual paralysis and death.
When these motor neurons die, the brain or spinal cord can no longer control the muscles that each motor neuron affects, leading to atrophy. This usually starts in the legs, hands, or vocal chords, but the symptoms are different for each patient.
Scientists and researchers have proposed several theories to explain ALS. One conjecture is that certain environmental toxins trigger this syndrome, due to the fact that some places with high pollution sometimes have higher incidence rates of ALS. Many researchers also think it may be an autoimmune disease, where the body’s own antibodies attack the body by mistake. However, this theory is unsubstantiated as well. Scientists have already found a specific genetic mutation that could be responsible for familial ALS, where numerous other family members are also diagnosed with the syndrome, but this form is found in only one-fifth of the total patients who have ALS. Genes seem to trigger some familial forms of ALS. In 1993, researchers found a gene in chromosome 21, ALS2, which causes one form. Healthy ALS2 genes kill free radicals, which are very reactive short-lived molecules that have one or more unpaired electrons. Free radicals are products of cell processes and are very harmful to cells. Scientists think that a mutated form of the gene kills chains of nerve cells. This picture shows the hands of a person who has ALS.