Alternative titles; symbols
HGNC Approved Gene Symbol: SLC30A10
SNOMEDCT: 702377007;
Cytogenetic location: 1q41 Genomic coordinates (GRCh38) : 1:219,910,445-219,959,098 (from NCBI)
| Location | Phenotype |
Phenotype MIM number |
Inheritance |
Phenotype mapping key |
|---|---|---|---|---|
| 1q41 | Hypermanganesemia with dystonia 1 | 613280 | Autosomal recessive | 3 |
Zinc functions as a cofactor for numerous enzymes, nuclear factors, and hormones and as an intra- and intercellular signal ion. Members of the zinc transporter (ZNT)/SLC30 subfamily of the cation diffusion facilitator family, such as SLC30A10, permit cellular efflux of zinc (Seve et al., 2004). The studies of Tuschl et al. (2012) and Quadri et al. (2012) indicated that the SLC30A10 protein functions as a manganese (Mn) transporter that protects the cell from Mn toxicity.
By searching databases with ZNT sequences, Seve et al. (2004) identified SLC30A10, which they called ZNT10. The deduced protein has a calculated molecular mass of 52.7 kD. It has 6 transmembrane helices, a basic region between helices 4 and 5, and cytoplasmic N and C termini. EST database analysis showed evidence of SLC30A10 expression only in fetal brain and fetal liver.
Quadri et al. (2012) found expression of the SLC30A10 gene in human liver. A punctate pattern of immunoreactivity was detected in the cytoplasm of the hepatocytes and in the epithelium of bile ducts. The plasma membrane facing the lumen of the bile ducts was also strongly immunoreactive. These findings were compatible with localization of SLC30A10 in different compartments of the secretory pathway, including the Golgi system, endosomes, and the plasma membrane. In the nervous system, the strongest immunoreactivity with a similar cytoplasmic punctate pattern was detected in the neurons in the globus pallidus. However, other neurons, such as the motoneurons of the spinal cord were also immunoreactive.
Seve et al. (2004) determined that the SLC30A10 gene contains 4 exons and spans 15 kb.
By genomic sequence analysis, Seve et al. (2004) mapped the SLC30A10 gene to chromosome 1q41.
In an in silico analysis of SLC30A10, Quadri et al. (2012) determined that the structure of the protein differed from that of known zinc transporters and was more consistent with it being a manganese transporter. Hepatocellular carcinoma cells exposed to manganese showed a 3-fold increase in SLC30A10 mRNA and protein, whereas exposure to zinc resulted in decreased SLC30A10 expression. These findings indicated that SLC30A10 is under tight control by extracellular manganese levels and that it functions as a manganese transporter in humans.
The yeast ortholog of SLC30A10 is Zrc1, which functions as a zinc transporter in yeast. Alignment of the protein sequences shows several amino acid changes between the 2 proteins, most of which affect highly conserved residues in SLC30A10. Lack of conservation of these amino acids suggests that Zrc1 and SLC30A10 evolved independently and function as 2 different transporters, with Zrc1 transporting zinc and SLC30A10 transporting manganese. This is consistent with normal zinc levels in patients with SLC30A10 mutations (Tuschl et al., 2012).
By homozygosity mapping followed by candidate gene analysis of 2 consanguineous families with hypermanganesemia with dystonia-1 (HMNDYT1; 613280), Tuschl et al. (2012) identified a deletion in the SLC30A10 gene (611146.0001) in the family reported by Tuschl et al. (2008). The other family had a large deletion encompassing exons 3 and 4 of the SLC30A10 gene. Subsequent mutation analysis in 6 additional families with the disorder identified homozygous mutations in all patients (see, e.g., 611146.0002-611146.0003). Parents for whom DNA was available for study were found to be heterozygous carriers. In vitro functional expression studies of 2 of the mutant proteins in a yeast strain lacking a manganese transporter demonstrated that both mutant proteins were nonfunctional, consistent with a loss of function.
Quadri et al. (2012) identified 2 different homozygous truncating mutations in the SLC30A10 gene (611146.0004 and 611146.0005, respectively) in affected members of 2 families with HMNDYT1. The phenotype was more pleomorphic in these families compared to those reported by Tuschl et al. (2012), with later onset and lack of severe liver involvement in some cases.
Hutchens et al. (2017) found that Slc30a10 -/- mice were born at the expected mendelian ratios and were indistinguishable from controls until postnatal day 16 to 18. After that, mutant mice were smaller than controls and died prematurely, and the phenotype was more evident and occurred earlier in males. Slc30a10 -/- mice had substantially elevated manganese levels and extensive morphologic alterations in thyroid. They suffered from hypothyroidism, with elevated thyroid-stimulating hormone levels and reduced thyroxine levels. A low-manganese diet rescued the phenotype of Slc30a10 -/- mice, indicating that manganese toxicity induced the failure-to-thrive and hypothyroidism phenotype. Although the magnitude of increase in manganese levels in thyroid was significantly greater than that in pituitary of Slc30a10 -/- mice, it was significantly less than the increase in brain, suggesting that elevated thyroid manganese might not be the only mechanism inducing hypothyroidism in Slc30a10 -/- mice.
Mercadante et al. (2019) found that Slc30a10 -/- mice did not consistently survive past 12 weeks of age. Slc30a10 -/- mice recapitulated the phenotype of human SLC30A10 deficiency by showing severe Mn excess with hepatosplenomegaly, increased brain weight, and decreased body weight. Slc30a10 -/- mice also had increased red blood cell count and mild thyroid pathology. Slc30a10 was essential not only for systemic Mn excretion, but also specifically for hepatobiliary Mn excretion, as Slc30a10 -/- mice had impaired systemic and biliary Mn excretion. Slc30a10 localized to the canalicular hepatocyte membrane and to the apical membrane of enterocytes. However, mice deficient in Slc30a10 specifically in hepatocytes or enterocytes, or in both cell types, exhibited minimal Mn excess and did not recapitulate human SLC30A10 deficiency, as seen in Slc30a10 -/- mice, suggesting that Slc30a10 expression in other sites likely compensates for impaired Mn excretion in hepatocytes and enterocytes. Expression of Slc30a10 in both hepatocytes and enterocytes of small intestine contributed to regulation of Mn levels, as hepatocyte Slc30a10 was essential for biliary Mn excretion, whereas enterocyte Slc30a10 was required for Mn excretion by enterocytes in small intestines.
In an Arab girl, born of consanguineous parents, with hypermanganesemia with dystonia-1 (HMNDYT1; 613280) reported by Tuschl et al. (2008), Tuschl et al. (2012) identified a homozygous 9-bp deletion (c.314_322del) in exon 1 of the SLC30A10 gene, resulting in deletion of ala105 to pro107 (ala105_pro107del) in the protein. The mutation was found by homozygosity mapping followed by candidate gene analysis. Both unaffected parents were heterozygous for the mutation, which was not found in 200 controls.
Carmona et al. (2019) showed that Mn accumulated in the Golgi of cells transfected with the ala105_pro107del SLC30A10 mutant. In contrast, cells expressing wildtype SLC30A10 showed low Mn, indicating effective Mn efflux. In cells expressing the SLC30A10 mutant, Mn was mostly found in single vesicles of Golgi, where it became toxic.
In 3 Arab sisters, born of consanguineous parents, with hypermanganesemia with dystonia-1 (HMNDYT1; 613280), Tuschl et al. (2012) identified a homozygous 266T-C transition in exon 1 of the SLC30A10 gene, resulting in a leu89-to-pro (L89P) substitution in a highly conserved residue. The mutation was not found in 200 controls. In vitro functional expression studies in a yeast strain lacking a manganese transporter demonstrated that the L89P mutant protein was nonfunctional.
In a patient with hypermanganesemia with dystonia-1 (HMNDYT1; 613280) originally reported by Gospe et al. (2000), Tuschl et al. (2012) identified a homozygous 1-bp deletion (585del) in exon 1 of the SLC30A10 gene, resulting in a frameshift and a truncated protein of 213 amino acids (Thr196ProfsTer17). The mutation was not found in 200 controls. In vitro functional expression studies in a yeast strain lacking a manganese transporter demonstrated that the mutant protein was nonfunctional. The phenotype of the patient was dominated by spastic paraparesis and micronodular cirrhosis, and polycythemia.
In 2 Dutch brothers with hypermanganesemia with dystonia-1 (HMNDYT1; 613280), Quadri et al. (2012) identified a homozygous 1-bp deletion (507delG) in exon 1 of the SLC30A10 gene, predicted to result in a frameshift and premature termination. The mutation was not found in the 1000 Genomes Project, the Exome Variant Server database, or in 668 control chromosomes. The brothers also carried a homozygous 500T-C transition in exon 1, which would result in a phe167-to-ser (F167S) substitution if translated; however, mRNA was not available for analysis. These patients had onset of gait disturbances at ages 14 and 2 years, respectively. Both developed dystonia and became wheelchair-bound. Both also had polycythemia in childhood. Laboratory studies showed increased serum manganese and increased total iron binding capacity, but normal iron. Brain MRI of 1 showed no abnormalities, whereas the other had hyperintense lesions of the globus pallidus. Neither had liver involvement. However, their younger sister, whose DNA was not available, died at age 46 of liver cirrhosis, portal hypertension, splenomegaly, and hepatic encephalopathy. She developed gait difficulties at the age of about 10, but there was no clear documentation of dystonia. Manganese levels were never determined, and neuroimaging was never performed. Liver biopsy from the sister showed almost complete absence of SLC30A10 immunoreactivity.
In 2 Italian brothers, born of consanguineous parents, with hypermanganesemia with dystonia-1 (HMNDYT1; 613280), Quadri et al. (2012) identified a homozygous 1-bp deletion (1235delA) in exon 4 of the SLC30A10 gene, resulting in a frameshift and premature termination. The mutation was not found in the 1000 Genomes Project or Exome Variant Server databases or in 996 control chromosomes. The brothers presented at age 47 and 57 years, respectively, with parkinsonism, including gait disturbances, bradykinesia, hypomimia, rigidity, and postural instability. Both also had polycythemia, hepatomegaly, and brain MRI lesions in the basal ganglia, midbrain, thalamus, cerebellum, and corticospinal tract. One patient had a sensorimotor axonal polyneuropathy. Laboratory studies showed markedly increased manganese, increased transferrin, and decreased ferritin. Chelation therapy resulted in clinical improvement.
Carmona, A., Zogzas, C. E., Roudeau, S., Porcaro, F., Garrevoet, J., Spiers, K. M., Salome, M., Cloetens, P., Mukhopadhyay, S., Ortega, R. SLC30A10 mutation involved in parkinsonism in manganese accumulation within nanovesicles of the Golgi apparatus. ACS Chem. Neurosci. 10: 599-609, 2019. [PubMed: 30272946] [Full Text: https://doi.org/10.1021/acschemneuro.8b00451]
Gospe, S. M., Jr., Caruso, R. D., Clegg, M. S., Keen, C. L., Pimstone, N. R., Ducore, J. M., Gettner, S. S., Kreutzer, R. A. Paraparesis, hypermanganesaemia, and polycythaemia: a novel presentation of cirrhosis. Arch. Dis. Child. 83: 439-442, 2000. [PubMed: 11040156] [Full Text: https://doi.org/10.1136/adc.83.5.439]
Hutchens, S., Liu, C., Jursa, T., Shawlot, W., Chaffee, B. K., Yin, W., Gore, A. C., Aschner, M., Smith, D. R., Mukhopadhyay, S. Deficiency in the manganese efflux transporter SLC30A10 induces severe hypothyroidism in mice. J. Biol. Chem. 292: 9760-9773, 2017. [PubMed: 28461334] [Full Text: https://doi.org/10.1074/jbc.M117.783605]
Mercadante, C. J., Prajapati, M., Conboy, H. L., Dash, M. E., Herrera, C., Pettiglio, M. A., Cintron-Rivera, L., Salesky, M. A., Rao, D. B., Bartnikas, T. B. Manganese transporter Slc30a10 controls physiological manganese excretion and toxicity. J. Clin. Invest. 129: 5442-5461, 2019. [PubMed: 31527311] [Full Text: https://doi.org/10.1172/JCI129710]
Quadri, M., Federico, A., Zhao, T., Breedveld, G. J., Battisti, C., Delnooz, C., Severijnen, L.-A., Di Toro Mammarella, L., Mignarri, A., Monti, L., Sanna, A., Lu, P., Punzo, F., Cossu, G., Willemsen, R., Rasi, F., Oostra, B. A., van de Warrenburg, B. P., Bonifati, V. Mutations in SLC30A10 cause parkinsonism and dystonia with hypermanganesemia, polycythemia, and chronic liver disease. Am. J. Hum. Genet. 90: 467-477, 2012. [PubMed: 22341971] [Full Text: https://doi.org/10.1016/j.ajhg.2012.01.017]
Seve, M., Chimienti, F., Devergnas, S., Favier, A. In silico identification and expression of SLC30 family genes: an expressed sequence tag data mining strategy for the characterization of zinc transporters' tissue expression. BMC Genomics 5: 32, 2004. Note: Electronic Article. [PubMed: 15154973] [Full Text: https://doi.org/10.1186/1471-2164-5-32]
Tuschl, K., Clayton, P. T., Gospe, S. M., Jr., Gulab, S., Ibrahim, S., Singhi, P., Aulakh, R., Ribeiro, R. T., Barsottini, O. G., Zaki, M. S., Del Rosario, M. L., Dyack, S., Price, V., Rideout, A., Gordon, K., Wevers, R. A., Kling Chong, W. K., Mills, P. B. Syndrome of hepatic cirrhosis, dystonia, polycythemia, and hypermanganesemia caused by mutations in SLC30A10, a manganese transporter in man. Am. J. Hum. Genet. 90: 457-466, 2012. Note: Erratum: Am. J. Hum. Genet. 99: 521 only, 2016. [PubMed: 22341972] [Full Text: https://doi.org/10.1016/j.ajhg.2012.01.018]
Tuschl, K., Mills, P. B., Parsons, H., Malone, M., Fowler, D., Bitner-Glindzicz, M., Clayton, P. T. Hepatic cirrhosis, dystonia, polycythaemia and hypermanganesaemia--a new metabolic disorder. J. Inherit. Metab. Dis. 31: 151-163, 2008. [PubMed: 18392750] [Full Text: https://doi.org/10.1007/s10545-008-0813-1]