With regard to the clinical phenotypes of the six ALS patients with pathogenic HREs in C9orf72, only two presented memory impairment and abnormal behavior, while the remaining four showed pure ALS without memory impairment, which emphasizes the need to test for HREs in C9orf72 in ALS patients with pure motor neuron signs. The gene discussed is C9orf72; the disease is memory impairment.