Since aberrant spliced HTT exon1‐intron1 mRNA, such as HTT1a, is present in HD KI mice and can be translated to exon1 mutant Htt in HD mice (Sathasivam et al., 2013) and in post‐mortem brains and fibroblast cultures from HD patients (Ly et al., 2022; Neueder et al., 2017), we wanted to explore whether cytoplasmic TDP‐43 can promote the generation of Htt exon1‐intron1 mRNA. This evidence concerns the gene HTT and Huntington disease.