TABLE 2.

Classification of different subtypes of inherited hemochromatosis detailing genetic loci and gene product function

ClassificationMutant gene productGene locusOMIMFunction
Type 1 (most common)Protein encoded by hfe6p21.3235200Duodenal crypt body iron sensor
Type 2 (juvenile)Unknown1q21602390Unknown
HAMP19q13606464Hepcidin antimicrobial peptide
Type 3TFR27q22604250Low-affinity transferrin receptor
Type 4Ferroportin 1/IREG1/MTP1 (SLC11A3)2q32604653/606069Intestinal iron exporter ferroportin 1
Type 5H-ferritin11q12-q13134770Ferritin heavy chain 1 (FTH1)