Since HNRNPA1 overexpression promoted fetal splicing, the expression of hnRNP genes implicated in several microsatellite expansion diseases, including amyotrophic lateral sclerosis and frontotemporal dementia and DM1, was examined using existing RNA-seq datasets of human muscle differentiation (22) and compared with control skeletal muscle from the DM deep sequencing data repository (http://dmseq.org/). The gene discussed is HNRNPA1; the disease is amyotrophic lateral sclerosis.