SPG20

Spartin is a is_associated_with::protein that in humans is encoded by the SPG20 is_associated_with::gene.

Background
The original description of this gene mutation and associated symptoms were described in 1967. This mutation is commonly found in high frequency with the Amish population. Newer studies have found that the mutation is not isolated to the Amish population, but also resides in the Omani population.

Presentation
This syndrome is not only characterized by is_associated_with::spasticity and weakness in the lower limbs, but also with is_associated_with::dysarthria, is_associated_with::mental retardation or mild developmental delay, and muscle wasting or is_associated_with::muscle atrophy.

Physical
Individuals appear to have difficulty walking, and report a clumsy, spastic gait which worsens over time. Some additional common physical features include overgrowth of the jaw bone, hammer toes, hand and feet abnormalities, and is_associated_with::pes cavus.

Cognitive
Cognitive challenges, including developmental delay and difficulty with performance in school, may affect individuals with this syndrome.

Neurologic
Neurologic examination of individuals with this mutation may show is_associated_with::dysmetria in the upper extremities, is_associated_with::hyperreflexia, distal amyotrophy and ankle is_associated_with::clonus, in addition to is_associated_with::spasticity, weakness and is_associated_with::dysarthria.

Diagnostic Imaging
The cerebellar vermis may present with mild atrophy and a loss of white matter volume.

Through Lifespan
Facial dysmorphism and subtle skeletal features are common in younger children. The condition progressively worsens, as is_associated_with::spasticity and distal amyotrophy symptoms are revealed more in teenage years. SPG20 expression in the adult is relatively modest, however it is widespread in the nervous system. Longitudinal comparison of magnetic resonance imaging concluded that there was a progression of the syndrome; thus, the condition appears to worsen over time.