Based on the clinicopathological diagnosis of Leigh-like subacute necrotizing encephalopathy (SNE) in all examined Yorkshire terriers and the similarities to the recessively inherited conditions in SNE-affected Alaskan husky dogs and THMD2-affected humans, as well as the available pedigree information of the two SNE-affected siblings, a recessive mode of inheritance was postulated. Here, SLC19A3 is linked to Leigh syndrome.