Inborn Errors of Metabolism

Inborn errors of metabolism (IEMs) are a large class of genetic disorders characterized by disruption of cellular biochemical functions. Although individual IEMs are rare, collectively they represent a large and diverse class of genetic conditions, with new disorders and disease mechanisms being described regularly. Advances in the understanding of the molecular and biochemical etiologies of many IEMs via modalities such as whole-exome sequencing and metabolomics have led to significant progress in detection and treatment in recent years. In this review, we examine the current state of newborn screening for IEMs, recent advances in therapy for IEMs (including glutaric aciduria type I, urea cycle disorders, mitochondrial disorders, and lysosomal storage disorders), and opportunities for further exploration and discovery.