Motor neuron diseases

Motor neuron diseases (MND) are a group of conditions that lead to the gradual degeneration of motor neurons, which are responsible for controlling voluntary muscle movements in the body. These diseases can impact both the lower motor neurons (which govern movements in the limbs and trunk) and the upper motor neurons (which start in the brain and send signals through the spinal cord).

Several types of genetic motor neuron diseases include:

Infantile Progressive Spinal Muscular Atrophy (SMA1): A severe form of SMA that begins in infancy, affecting the muscles used for breathing and swallowing, often leading to serious complications within the first two years of life.

Intermediate Spinal Muscular Atrophy (SMA2): Typically starts after six months of age and impacts the muscles used for sitting and standing.

Juvenile Spinal Muscular Atrophy (SMA3): A milder form of SMA that begins in early childhood and affects muscles used for walking and other activities.

Adult Spinal Muscular Atrophy: This form of SMA may develop in adulthood and primarily affects limb muscles.

The most prevalent form of motor neuron disease is known as amyotrophic lateral sclerosis (ALS), also referred to as Lou Gehrig's disease. This condition is characterized by the degeneration of both upper and lower motor neurons, resulting in the progressive loss of muscle control and function. Unlike other genetic motor neuron diseases, ALS is typically not inherited and its exact cause is still unknown.