title: Identification of novel mutations in hemochromatosis genes by targeted next generation sequencing in Italian patients with unexplained iron overload.
abstract: Hereditary hemochromatosis, one of the commonest genetic disorder in Caucasians, is mainly associated to homozygosity for the C282Y mutation in the HFE gene, which is highly prevalent (allele frequency up to near 10% in Northern Europe) and easily detectable through a widely available "first level" molecular test. However, in certain geographical regions like the Mediterranean area, up to 30% of patients with a HH phenotype has a negative or non-diagnostic (i.e. simple heterozygosity) test, because of a known heterogeneity involving at least four other genes (HAMP, HJV, TFR2, and SLC40A1). Mutations in such genes are generally rare/private, making the diagnosis of atypical HH essentially a matter of exclusion in clinical practice (from here the term of "non-HFE" HH), unless cumbersome traditional sequencing is applied. We developed a Next Generation Sequencing (NGS)-based test targeting the five HH genes, and applied it to patients with clinically relevant iron overload (IO) and a non-diagnostic first level genetic test. We identified several mutations, some of which were novel (i.e. HFE W163X, HAMP R59X, and TFR2 D555N) and allowed molecular reclassification of "non-HFE" HH clinical diagnosis, particularly in some highly selected IO patients without concurring acquired risk factors. This NGS-based "second level" genetic test may represent a useful tool for molecular diagnosis of HH in patients in whom HH phenotype remains unexplained after the search of common HFE mutations.
authors.affiliation: Department of Medicine, Section of Internal Medicine, University of Verona, Verona, Italy.
authors.forename: Sadaf
authors.initials: S
authors.lastname: Badar
authors.affiliation: Department of Medicine, Section of Internal Medicine, University of Verona, Verona, Italy.
authors.forename: Fabiana
authors.initials: F
authors.lastname: Busti
authors.affiliation: Department of Biotechnology, University of Verona, Verona, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Ferrarini
authors.affiliation: Department of Biotechnology, University of Verona, Verona, Italy.
authors.forename: Luciano
authors.initials: L
authors.lastname: Xumerle
authors.affiliation: Department of Medicine, Section of Internal Medicine, University of Verona, Verona, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Bozzini
authors.affiliation: Unit of Pathology, Azienda Ospedaliera Universitaria Integrata Verona, Verona, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Capelli
authors.affiliation: Department of Diagnostics and Public Health, Section of Radiology, University of Verona, Verona, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Pozzi-Mucelli
authors.affiliation: Department of Medicine, Section of Internal Medicine, University of Verona, Verona, Italy.
authors.forename: Natascia
authors.initials: N
authors.lastname: Campostrini
authors.affiliation: Unit of Clinical Chemistry, Azienda Ospedaliera Universitaria Integrata Verona, Verona, Italy.
authors.forename: Giovanna
authors.initials: G
authors.lastname: De Matteis
authors.affiliation: Department of Biotechnology, University of Verona, Verona, Italy.
authors.forename: Sergio
authors.initials: S
authors.lastname: Marin Vargas
authors.affiliation: Department of Biotechnology, University of Verona, Verona, Italy.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Giorgetti
authors.affiliation: Department of Biotechnology, University of Verona, Verona, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Delledonne
authors.affiliation: Department of Medicine, Section of Internal Medicine, University of Verona, Verona, Italy.
authors.forename: Oliviero
authors.initials: O
authors.lastname: Olivieri
authors.affiliation: Department of Medicine, Section of Internal Medicine, University of Verona, Verona, Italy.|Veneto Regional Referral Center for Iron Metabolism Disorders, GIMFer (Gruppo Interdisciplinare Sulle Malattie Del Ferro), Azienda Ospedaliera Uiversitaria Integrata Verona, Verona, Italy.
authors.forename: Domenico
authors.initials: D
authors.lastname: Girelli
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers; D001706:Biopsy; D004252:DNA Mutational Analysis; D005260:Female; D005820:Genetic Testing; D006432:Hemochromatosis / Q000150:complications / Q000175:diagnosis* / Q000235:genetics*; D000071020:Hemochromatosis Protein; D064451:Hepcidins / Q000235:genetics; D059014:High-Throughput Nucleotide Sequencing; D015395:Histocompatibility Antigens Class I / Q000737:chemistry / Q000235:genetics; D006801:Humans; D019190:Iron Overload / Q000175:diagnosis* / Q000209:etiology*; D007558:Italy; D008099:Liver / Q000378:metabolism / Q000473:pathology; D008297:Male; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics; D015201:Meta-Analysis as Topic; D008875:Middle Aged; D008958:Models, Molecular; D009154:Mutation; D011487:Protein Conformation; D011990:Receptors, Transferrin / Q000737:chemistry / Q000235:genetics
chemical_list: D015415:Biomarkers; C578702:HAMP protein, human; C103673:HFE protein, human; D000071020:Hemochromatosis Protein; D064451:Hepcidins; D015395:Histocompatibility Antigens Class I; D008565:Membrane Proteins; D011990:Receptors, Transferrin; C503640:TFR2 protein, human