TBC1D1 and amyotrophic lateral sclerosis: In ALS cases, we detected significantly different inclusion of one exon (exon 19 of PPFIBP1) in the lumbar and cervical spinal cord but not in the motor cortex, while in motor cortex, we saw enhanced skipping of both alternative exons within TBC1D1 (Fig. 9b, Supplementary Data 6).