CD44 and amyotrophic lateral sclerosis: Sporadic ALS accounts for about 90% of cases of the disease, whereas about 10% of ALS cases are hereditary due to genetic variants in numerous genes, including: the chromosome 9 open reading frame 72 (C9ORF72), Cu/Zn superoxide dismutase (SOD1), TAR DNA-binding protein 43 (TDP-43), and fused-in sarcoma/translocated liposarcoma (FUS/TLS) genes.