SPARC and amyotrophic lateral sclerosis: Several genes identified within the clusters, such as CD44, NDRG2, GSN, and CDK2 in motor neurons (Katzeff et al., 2020, 2020; Matsumoto et al., 2012; Moujalled et al., 2015; Rohm et al., 2019), and PRNP, PABPC1, SPARC, and IRS1 in muscle tissue (Collins et al., 2015; Gao et al., 2023; Halbgebauer et al., 2022; Uozumi et al., 2024), have been previously linked to ALS pathogenesis.