The role of C9orf72 in protein trafficking was further demonstrated in the human spinal cord of an ALS patient (with a C9ORF72-intronic repeat expansion mutation), where an increased proportion of motor neurons showed the colocalization of C9orf72 with Rab 5, Rab 7, and Rab 11 (when compared to healthy individuals), possibly resulting in the dysregulation of endosomal trafficking [70]. Here, C9orf72 is linked to amyotrophic lateral sclerosis.