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).
Amüotroofsel lateraalskleroosil on tavaliselt kolm alaliiki: juhuti esinev (kõige enam esinev), perekondlik (5 – 10 protsenti juhtudest) ning Guami taustaga (suurel arvul haigestumisi on toimunud Guamis ja Vaikse ookeani regiooni ÜRO hooldusalusel territooriumil).