TPPP and amyotrophic lateral sclerosis: Among the highly prioritized genes in which mutations have not yet been identified, we observed a number of highly interesting genes, including CCS (position 2), RNF19A (position 5), DERL1 (position 6), and XRN2 (position 10) for ALS, and KLK6 (position 7), SLC6A3 (position 8), and TPPP (position 9) for PD.