Prenatal Diagnosis of Inborn Errors of Metabolism

Inborn errors of metabolism are inherited conditions where there is a defect or block in a metabolic pathway leading to the accumulation of metabolite(s) proximal to the defect and a metabolic deficit distal to this (1). The defect usually results from a specific enzyme deficiency; however, defects in enzyme cofactors or activators/stabilisers can also lead to an enzyme deficiency in vivo. There might also be defects in certain transporter systems, at the plasma membrane level or within cellular compartments, which will also lead to metabolic disorders.