Background: Hepatic involvement is a common feature in childhood mitochondrial disorders. Deoxyguanosine kinase (DGUOK) deficiency is one of the mitochondrial DNA depletion syndromes associated with hepatocerebral syndrome. Hepatic disease and neurologic dysfunction occurs within weeks after birth. Low birth weight is one of the common features. This study aims to describe the clinical and laboratory features of four infants carrying four different pathogenic variants in the DGUOK gene.