C9orf72 and amyotrophic lateral sclerosis: The overlap between Amyotrophic Lateral Sclerosis (ALS) and Frontotemporal Dementia (FTD) represents a significant genetic convergence point of clinical and pathological relevance [2].A prevalent genetic etiology for both ALS and FTD is the pathogenic amplification of STRs within the C9orf72 intron [2].