Mitochondrial DNA Depletion Syndromes Presenting in Childhood

Maintaining mitochondrial DNA content and integrity is essential for normal mitochondrial function. A growing number of childhood-onset mitochondrial DNA depletion syndromes have been described where the processes that typically function to ensure adequate mitochondrial DNA content are impaired. Here, we present an illustrative clinical case of an infant with a mitochondrial DNA depletion syndrome. We also review the various molecular defects that can underlie this group of conditions and summarize important clinical considerations in their diagnosis and management.