Similarly, mutations in SPG7 already known to cause a wide disease spectrum including autosomal recessively inherited spastic paraplegia type 7 [22], adult-onset ataxia [23], sporadic adult-onset UMN syndrome [24], chronic progressive external ophthalmoplegia [25], and autosomal dominantly inherited optic neuropathy [19], may also be linked to ALS. Here, SPG7 is linked to External ophthalmoplegia.