3-Methylcrotonyl-coenzyme A carboxylase deficiency in Amish/Mennonite adults identified by detection of increased acylcarnitines in blood spots of their children

Isolated 3-methylcrotonyl coenzyme A carboxylase (MCC) deficiency was documented in four adult women from the Amish/Mennonite population of Lancaster County, Pennsylvania. Metabolic and enzymatic investigations in these individuals were instituted after the detection of abnormal acylcarnitine profiles in blood spots obtained from their newborn children, in whom MCC activity was normal.