In addition, there was no difference in cryptic HDGFL2 signal ratios between males and females in control (P = 0.91), presymptomatic C9orf72 mutation carrier (P = 0.30), symptomatic C9orf72 mutation carrier (P = 0.08), or sporadic ALS (P = 0.46) groups. This evidence concerns the gene HDGFL2 and amyotrophic lateral sclerosis.