C9orf72 and amyotrophic lateral sclerosis: Other genes with reduced expression in nop56−/− were c9orf72, fus, tardbp (genes related to ALS), zpld1a, zpld1b (genes involved in the development of the cupula of the inner ear, which is responsible for balance) and ptf1a, grid2 and cbln12 (expressed in the zebrafish cerebellum).