In the non-coding region of C9orf72 gene, a polymorphic GGGGCC hexanucleotide repeat was found, that was detected in controls only in a few copies (less than 23 repeats), whereas in patients suffering from ALS and FTLD it was found in at least a few hundred (estimated around 700–1600) [6]. Here, C9orf72 is linked to amyotrophic lateral sclerosis.