Spastic paraplegia 31

Spastic paraplegia 31, also called SPG31, is a rare type of hereditary spastic paraplegia marked by sensation anomalies of the lower limbs. Symptoms usually begin either in childhood or in mid-adulthood, around age 30, and include weakness of the proximal lower limbs, brisk reflexes and a spastic gait. A more complex form adds peripheral neuropathy, bulbar palsy, dysarthria, dysphagia and impaired vibration sense in the distal limbs. It is caused by autosomal dominant mutations in the REEP1 gene on chromosome 2, which leave a short, nonfunctional protein that is quickly broken down. Diagnosis rests on gene sequencing, electrophysiological studies and examination, and walking support and physical therapy manage the impairment.