The Molecular Spectrum of β- and α-Thalassemia Mutations in Non-Endemic Umbria, Central Italy.

The aim of this study was to describe the mutational spectrum of hemoglobinopathies during the period 1988-2015 in Umbria, Central Italy, which has never been considered endemic for these conditions. Twenty-four different β-globin gene mutations were identified in 188 patients and eight different α-globin gene mutations in 74 patients. Sixty percent β-thalassemia (β-thal), 85.0% sickle cell disease, 44.0% Hb S (HBB: c.20A>T)/β-thal and 85.0% compound heterozygotes for hemoglobin (Hb) variant-carrying patients were diagnosed or molecularly characterized in the last 3 years. Moreover, most homozygous or compound heterozygous patients (84.5%) came from foreign countries, while only 15.5% were of Italian origin. These data are in accordance with the increasing foreign resident population in Umbria, which has nearly doubled in 10 years (2004-2014). Different from β-globin gene variations, no increasing trend in α defects was observed in our study cohort. Consistently, 58.0% of patients have an Italian origin, suggesting no broad influence of foreign migration in the α-globin genes genetic background. As few defects are prevalent in each country of origin or ethnic group, their knowledge may provide a proper strategy for the identification of mutations in immigrant individuals in a non-endemic region and be important for carrier identification and prenatal screening.