ETHE1

The ETHE1 gene encodes ethylmalonic encephalopathy protein 1, also known as HSCO. It acts as a mitochondrial thiosulfate sulfurtransferase, catalyzing thiosulfate conversion to sulfide and sulfate. This maintains cellular sulfur homeostasis and protects against hydrogen sulfide (H₂S) toxicity, which impairs mitochondrial energy metabolism.
Mutations in ETHE1 cause ethylmalonic encephalopathy (EE), an autosomal recessive disorder with metabolic acidosis and neuroregression. Relevant pathways involve mitochondrial oxidative stress and energy balance. No targeted drugs exist yet; care is supportive, while preclinical research explores coenzymes, antioxidants, or gene therapy as potential interventions.