SLC30A10 and polycythemia: By contrast, mutations in slc39a14 produce an autosomal recessive hypermanganesemia with earlyonset parkinsonism-dystonia.12 Pathogenic variants of SLC30A10 (ZnT10) cause hypermanganesemia with dystonia, polycythaemia and chronic liver disease (sometimes termed SLC30A10-related manganism), a disorder featuring neurologic movement disorder (dystonia/parkinsonism), very high serum Mn, hepatic fibrosis/cirrhosis and erythrocytosis.13–15