Genetics of Human Zinc Deficiencies

Abstract

Abstract The numerous mutations in two families of human zinc transporters (SLC30, 10 ZNT proteins and SLC39, 14 ZIP proteins) indicate that the inherited diseases established for ZIP4 (acrodermatitis enteropathica), ZIP13 (spondylocheirodysplastic Ehlers–Danlos syndrome), ZNT2 (transient neonatal zinc deficiency) and ZNT10 (manganism) signify an emerging field that is important for a wide variety of diseases. Discoveries also impact nutrition and toxicology as differences in requirements for zinc and sensitivities towards an excess of zinc are genetically determined. The spectrum of mutations leads to phenotypes of different severity and risk factors for diseases. Some mutations are rare but others such as the ones in ZNT2 and ZNT8 (the latter associated with diabetes risk) are important for the health of majorities in populations. Inherited diseases of zinc metabolism are also due to mutations in other genes. As metal ions interact and their concentrations are balanced, mutations affect the metabolism of metals ions other than zinc as already shown for manganese, iron and toxic metal ions such as cadmium. Key Concepts Zinc is involved in virtually all biological processes. Zinc transporters, metallothioneins and other proteins are involved in inherited diseases of zinc metabolism with a large spectrum of phenotypes. Two members of the human zinc transporter family ZNT (SLC30) have mutations that lead to inherited diseases: ZNT2 (transient neonatal zinc deficiency) and ZNT10 (manganism) – the list is likely to grow. Two members of the human zinc transporter family ZIP (SLC39) have mutations that lead to inherited diseases: ZIP4 (acrodermatitis enteropathica) and ZIP13 (spondylocheirodysplastic Ehlers–Danlos syndrome) – the list is likely to grow. Genome‐wide association studies (GWASs) reveal relationships between zinc transporters and a wide range of diseases. Some associations between zinc transporters and diseases affect large fractions of populations. Mutations in bona fide zinc transporters affect the metabolism of other metal ions and possibly other trace elements, for example, selenium.