There are three common classifications of ALS: sporadic (the most common), familial (about 5 to 10 percent of cases have a family history), and Guamanian (a high number of cases have occurred in Guam and the trust territories of the Pacific).
Ada tiga jenis ALS yang umum: sporadis (paling umum), familia (sekitar 5 sampai 10 persen kasusnya berkaitan dengan sejarah kesehatan keluarga), dan Guam (sebagian kasusnya muncul di Guam dan daerah perwalian Pasifik).