It was shown that the unnatural dipeptide repeat (DPR) proteins (poly(glycine-alanine), polyGA; poly(glycine-arginine), polyGR; poly(proline-alanine), polyPA; poly(proline-arginine), polyPR; and poly(glycine-proline), polyGP) generated as a result of the hexanucleotide (GGGGCC) repeat expansion in the gene chromosome 9 open reading frame 72 (C9ORF72), which is considered now as the most common cause of ALS and frontotemporal dementia (FTD), were able to alter the liquid-like state of PMLOs [161]. This evidence concerns the gene C9orf72 and frontotemporal dementia.