Gene mutation one cause of spinal muscular atrophy

Fatal spinal muscular atrophies (SMA) involve all motor neurons, but non-fatal SMA with lower extremity predominance (SMA-LED) only affects nerve cells that control leg muscles. Researchers from Cedars-Sinai Medical Center recently conducted a study on the gene mutations possibly responsible for this inherited disease. DYNC1H1 is a molecule inside cells that acts as a motor to transport cellular components. This study determined that a genetic mutation disrupts this motor function. Developmental delay and weakness were also found in some subjects, indicating the brain may also be affected. Dr. Robert H. Baloh, director of Cedars-Sinai Medical Center's Neuromuscular Division said that this research indicates that a range of DYNC1H1-related diseases exist in humans, from neurodevelopmental abnormality of the central nervous system to involvement of motor neurons, which manifests as spinal muscular atrophy.