SMN1 and amyotrophic lateral sclerosis: Furthermore, the research field of biomarkers, besides supporting diagnosis it is important i) for evaluating the efficacy of new molecules, and ii) for revealing both specific and cross-disease pathological mechanisms: for this reason, it is largely exploited for neurodegenerative disorders such as SMA, ALS, and AD (Lanni et al., 2010; Stanga et al., 2012; Kariyawasam et al., 2018; Stanga et al., 2018a; Stanga et al., 2018b).