Two new human DMT1 gene mutations in a patient with microcytic anemia, low ferritinemia, and liver iron overload

Blood. 2006 May 15;107(10):4168-70. doi: 10.1182/blood-2005-10-4269. Epub 2006 Jan 26.

Abstract

DMT1 mediates the pH-dependent uptake of Fe(2+) from the diet in duodenal enterocytes and in most other cells. It transfers iron from the endosomes to the cytosol following the uptake of the transferrin-transferrin receptor complex. DMT1 mutations are responsible for severe hypochromic microcytic anemia in rodents and in 2 human patients described recently. We report a compound heterozygote for 2 new DMT1 mutations, associated with microcytic anemia from birth and progressive liver iron overload. The first mutation is a GTG deletion in exon 5, leading to the V114 in-frame deletion in transmembrane domain 2, and the second is a G --> T substitution in exon 8 leading to the G212V replacement in transmembrane domain 5. Together with the 2 previously reported cases, this patient defines a new syndrome of congenital microcytic hypochromic anemia, poorly responsive to oral iron treatment, with liver iron overload associated paradoxically with normal to moderately elevated serum ferritin levels.

Publication types

  • Case Reports
  • Comparative Study

MeSH terms

  • Amino Acid Sequence
  • Anemia / genetics*
  • Animals
  • Cation Transport Proteins / genetics*
  • Child
  • Conserved Sequence
  • Female
  • Ferritins / blood*
  • Ferritins / deficiency*
  • Humans
  • Iron Overload / genetics*
  • Liver / metabolism*
  • Male
  • Molecular Sequence Data
  • Mutation*
  • Pedigree
  • Sequence Alignment
  • Sequence Homology, Amino Acid

Substances

  • Cation Transport Proteins
  • solute carrier family 11- (proton-coupled divalent metal ion transporters), member 2
  • Ferritins