ER membrane-shaping proteins, such as RTN2, ATL1, Spastin, REEP1, and ARL6IP1, have been found to cause an inherited neurological disorder termed hereditary spastic paraplegia (HSP), a disease presented by muscle spasticity, outlining the critical nature of functional ER membrane dynamics for neuron survival (Hübner and Kurth, 2014). Here, SPAST is linked to hereditary spastic paraplegia.