Amyotrophic lateral sclerosis (ALS) is a devastating neurological disorder which always results in death. This condition is often called Lou Gehrig’s disease after the American baseball player Henry Louis “Lou” Gehrig who died from disease complications in 1941 at the age of 37. In ALS nerve cells are damaged in a rapidly progressive fashion resulting in paralysis of all muscles. The usual cause of death is collapse of the respiratory system when these muscles become involved. Disease incidence peaks around the age of 60 and men are more commonly affected than women.

Currently, there is no known cure for ALS and the medication riluzole (Rilutek) is the only one approved for use by the Food and Drug Administration (FDA) for treatment. This drug slows progression of the disease by lowering the release of glutamate and reducing the rate of damage to neurons. However, this drug has not been exceedingly effective, with most persons dying within 5 years of diagnosis.

New hope is on the horizon with the results of recent studies reported in Science. Scientists at the University of Massachusetts Medical School and King’s College in London report that they have identified that at least one heritable form of ALS may be due to mutations in the FUS/TLS gene located on chromosome 16. Furthermore, similar mutations may account for between 5-10% of all inherited cases. The researchers found mutations in 17 different families with familial ALS while no mutations were found in cases of spontaneous ALS. Of note is the fact that these families all come from a single study group, with a highly conserved gene pool; they may not be typical of a larger population. The mutation causes proteins which should be transported into the cell nucleus to remain in the cytoplasm. Either the aggregation leads to cell death or the missing protein is necessary for healthy cell function but this is not yet clear. A total of 13 mutations were identified in the study population and with identification of the gene, therapy for the treatment of this fatal disease can be more directed and hopefully more effective.

References

Kwiatkowski, T., Bosco, D., LeClerc, A., Tamrazian, E., Vanderburg, C., Russ, C., Davis, A., Gilchrist, J., Kasarskis, E., Munsat, T., Valdmanis, P., Rouleau, G., Hosler, B., Cortelli, P., de Jong, P., Yoshinaga, Y., Haines, J., Pericak-Vance, M., Yan, J., Ticozzi, N., Siddique, T., McKenna-Yasek, D., Sapp, P., Horvitz, H., Landers, J., & Brown, R. (2009). Mutations in the FUS/TLS Gene on Chromosome 16 Cause Familial Amyotrophic Lateral Sclerosis Science, 323 (5918), 1205-1208 DOI: 10.1126/science.1166066

Vance, C., Rogelj, B., Hortobagyi, T., De Vos, K., Nishimura, A., Sreedharan, J., Hu, X., Smith, B., Ruddy, D., Wright, P., Ganesalingam, J., Williams, K., Tripathi, V., Al-Saraj, S., Al-Chalabi, A., Leigh, P., Blair, I., Nicholson, G., de Belleroche, J., Gallo, J., Miller, C., & Shaw, C. (2009). Mutations in FUS, an RNA Processing Protein, Cause Familial Amyotrophic Lateral Sclerosis Type 6 Science, 323 (5918), 1208-1211 DOI: 10.1126/science.1165942