ITPR2 and amyotrophic lateral sclerosis: Genome-wide association studies of sporadic ALS have implicated a number of genes or regions (DPP6, ITPR2, UNC13A, FGGY, ELP3, KIFAP3, 9p21.2) [3]–[11], but replication of these findings in independent populations has proven difficult [12]–[16].