A Clinical Update of the Hb Siirt [ß27(B9)Ala→Gly; HBB: c.83C>G] Hemoglobin Variant.

We report a clinical update of the hemoglobin (Hb) variant [ß27(B9)Ala→Gly; HBB: c.83C>G], named Hb Siirt, that was previously described as a silent variant in a 23-year-old Kurdish female. The patient was also a carrier of the codon 5 (-CT) (HBB: c.17_18delCT) frameshift mutation and of the ααα anti 3.7 triplication. Her initial moderate ß-thalassemia intermedia (ß-TI) phenotype worsened with time, causing the patient to become a transfusion-dependent subject at the age of ∼40 years. Subsequent molecular characterization of both parents revealed that the Hb Siirt variant was inherited by the mother, while the other two globin alterations (HBB: c.17_18delCT and αααanti 3.7 triplication) were genetically transmitted by the father. The latter remained a carrier of a mild ß-TI phenotype throughout his life, at least until the age of 65 years. We hypothesize that the worsened clinical conditions in the daughter were due to the additional, maternally inherited Hb Siirt variant. However, protein 3D conformational analysis did not seem to reveal substantial overall structural changes. Among the other three described variants [Hb Volga (HBB: c.83C>A), Hb Knossos (HBB: c.82 G>T), Hb Grange-Blanche (HBB: c.83C>T] that are due to nucleotide substitutions at codon 27 of the ß-globin gene; only Hb Knossos causes a ß+-thalassemia (ß+-thal) phenotype.

Epidemiology and screening of sickle cell anemia in the Mediterranean area and in developing countries.

This article reviews the epidemiology and screening of sickle cell anemia in the Mediterranean area and in developing countries. Its aim is to create awareness of the global health burden of this condition, which is one of the most common genetic diseases worldwide. The constantly growing incidence of this condition, also caused by recent migrations, has induced the World Health Organization to pressure national health systems to strengthen prevention programs and to recognize it as a public health problem. However, scarce financial resources hinder implementation of activities.

Carrier screening for inherited haemoglobin disorders among secondary school students and young adults in Latium, Italy.

To reduce the incidence of ß-thalassaemia major and other severe haemoglobin-related disorders by the early identification of healthy carriers, the Centro Studi Microcitemie Roma has been organising since 1975 a prevention programme in Latium, an Italian central region. This programme entails two different types of carrier screening on a voluntary basis: a universal screening offered to secondary school students and a screening offered to young adults. In 36 years of scholastic screening (from 1975 until 2011), 1,466,100 students have been examined and 26,786 (1.8 %) carriers of non-α thalassaemia have been identified. In the extra-scholastic screening, 388,690 adult subjects (including the carriers' relatives) have been examined and a total of 38,457 (9.9 %) carriers of non-α thalassaemia have been detected. These results demonstrate that the precocious identification of healthy carriers allowed the identification of at-risk couples and reduced to zero the birth of affected babies in the Latium native population. This programme does not involve huge resources and is relatively inexpensive and, as such, it is essential to be offered to the total Latium scholastic and extra-scholastic population, which is epidemiologically changing due to migratory fluxes from countries in which haemoglobin disorders are common.

Hb Filottrano [codon 120 (-A)]: a novel frameshift mutation in exon 3 of the ß-globin gene causing dominantly inherited ß-thalassemia intermedia.

We report a novel frameshift mutation in exon 3 of the ß-globin gene, that, in the heterozygous state, leads to a ß-thalassemia intermedia (ß-TI) phenotype (marked anemia, splenomegaly, hyperbilirubinemia, jaundice, unbalanced synthesis of α/non-α chains in a 34-year-old Italian woman. This frameshift mutation, due to the deletion of the first nucleotide (-A) at codon 120, results in a ß-globin chain that is elongated to 156 amino acid residues. These highly unstable abnormal chains precipitate in the erythroblasts as inclusion bodies, thus causing inefficient erythropoiesis and ultimately resulting in the observed dominant clinical phenotype.