TARDBP and amyotrophic lateral sclerosis: Our validation of POLDIP3 exon 3 exclusion in human ALS/FTD neuronal nuclei with loss of nuclear TDP-43 strongly supports POLDIP3 as a TDP-43 loss-of-function marker in ALS tissue, and indeed increased POLDIP3 variant 2 mRNA is seen in various motor regions of the CNS in ALS (Shiga et al., 2012).