HSP is caused by a variety of gene mutations, including genes specific for myelin (proteolipid protein), axonal transport (kinesis), smooth endoplasmic reticulum (reticulin) and mitochondria (heat shock protein 60, paraplegin, and mitofusin2) [6, 17, 48, 51, 81]. The gene discussed is SPG7; the disease is hereditary spastic paraplegia.