Methylmalonyl-Coa Epimerase Deficiency, also known as methylmalonic acidemia due to methylmalonyl-coa epimerase deficiency, is related to dystonia, dopa-responsive, due to sepiapterin reductase deficiency and propionic acidemia. An important gene associated with Methylmalonyl-Coa Epimerase Deficiency is MCEE (Methylmalonyl-CoA Epimerase). Related phenotypes are spasticity and failure to thrive