title: Significance of borderline hemoglobin A2 values in an Italian population with a high prevalence of beta-thalassemia.
abstract: We report a retrospective analysis carried out on 23,485 subjects submitted to a screening program from 2000 to 2006. Of these subjects, 3,934 had borderline HbA(2) values from 3.1 to 3.9%; 410 samples, analyzed previously using PCR methods and sequencing because all of these were partners of a carrier of classical beta-thalassemia, were selected for statistical analysis. Of 410 subjects, 94 (22.9%) were positive for a molecular defect in the beta-, delta- or alpha-globin genes. The most prevalent molecular defects were beta IVS1 nt 6 (HBB c.92+6T C), co-inheritance of severe beta thalassemia and delta mutations, beta-promoter mutations and triplication of alpha genes were detected; alpha-thalassemia and Hb-variants were also evident. Borderline HbA(2) is not a rare event in a population with a high prevalence of beta-thalassemia carriers. These data support the necessity to investigate these cases at a molecular level, particularly if the partner is a carrier of beta-thalassemia.
authors.affiliation: U.O.C. Ematologia II con Talassemia, Azienda Ospedaliera Vincenzo Cervello, via Trabucco 180, Palermo, Italy.
authors.forename: Antonino
authors.initials: A
authors.lastname: Giambona
authors.forename: Cristina
authors.initials: C
authors.lastname: Passarello
authors.forename: Margherita
authors.initials: M
authors.lastname: Vinciguerra
authors.forename: Rita
authors.initials: R
authors.lastname: Li Muli
authors.forename: Pietro
authors.initials: P
authors.lastname: Teresi
authors.forename: Maurizio
authors.initials: M
authors.lastname: Anzà
authors.forename: Gaetano
authors.initials: G
authors.lastname: Ruggeri
authors.forename: Disma
authors.initials: D
authors.lastname: Renda
authors.forename: Aurelio
authors.initials: A
authors.lastname: Maggio
mesh_terms: D006443:Hemoglobin A2 / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007558:Italy / Q000453:epidemiology; D017086:beta-Thalassemia / Q000097:blood* / Q000453:epidemiology*
chemical_list: D006443:Hemoglobin A2