Low activity or concentrations of racemases/epimerases (AMACR,37 methylmalonyl-CoA epimerase38) are associated with inherited errors in metabolism and may also be associated with stroke and dementia39 and neurodegenerative diseases,40 such as Amyotrophic Lateral Sclerosis (ALS, a.k.a. motor neurone disease, Lou Gehrig's disease). Here, AMACR is linked to amyotrophic lateral sclerosis.