We detected novel non-annotated TSSs on the sense and antisense strand at the C9orf72 locus suggesting new potential transcripts and we observed changes in the expression of the annotated and newly identified C9orf72 transcripts, not only in C9orf72-HRE patients, but also in FTD patients carrying mutations in the microtubule associated protein tau (MAPT) and granulin (GRN) genes. This evidence concerns the gene GRN and frontotemporal dementia.