Recently, an expanded hexanucleotide repeat (GGGGCC) within chromosome 9 open reading frame 72 (C9ORF72) has also been identified in a large percentage (23.5–46%) of patients with ALS and frontotemporal dementia (FTD), and additionally, mutations in profilin 1 (PFN1) have been reported in patients with ALS [4]–[6]. The gene discussed is PFN1; the disease is frontotemporal dementia.