ATP13A2 and hereditary spastic paraplegia: Biallelic homozygous ATP13A2 mutations were identified in three patients (representing 0.4% of HSP patients and 0.7% of families), including c.2473_2474insAAdelC;p.(Leu825Asnfs*32), c.2126G>C;p.(Arg709Thr), and c.2158G>T;p.(Gly720Trp).