Novel genetic variants of the Superoxide Dismutase 1, Soluble (Amyotrophic Lateral Sclerosis 1 (Adult)) (SOD1) gene are described. Various genotypes, haplotypes, and haplotype pairs that exist in the general United States population are disclosed for the SOD1 gene. Compositions and methods for haplotyping and/or genotyping the SOD1 gene in an individual are also disclosed. Polynucleotides defined by the sequence the haplotypes disclosed herein are also described
