Furthermore, a link to ALS has been suggested after a patient with FOSMN was found to harbor a heterozygous mutation in the familial ALS gene for SOD1. This specific mutation (D90A) generally causes a recessive form of ALS, although there are several pedigrees in which this mutation appears to cause disease in an autosomal dominant manner. This evidence concerns the gene SOD1 and amyotrophic lateral sclerosis.