THY1 and amyotrophic lateral sclerosis: However, an earlier study showed that transgenic mice expressing mutant SOD1 predominantly in the motor neuron do not develop ALS [64], while Lino and coworkers [65] showed that mutant SOD1 expression driven by the Thy-1 promoter neither produced an ALS phenotype nor affected the progression of mutant SOD1 Tg mice.