Characterization of Hb Lepore variants in the UK population.

A molecular study of Hb Lepore heterozygotes identified by the UK population screening program has revealed four out of the five known Lepore variants. The region of homologous δ- and ß-globin gene sequence was determined in 58 unrelated Hb Lepore heterozygotes referred for confirmation of their carrier status by DNA analysis through the national thalassemia and sickle cell screening program over a period of 10 years. The most common variant found was Hb Lepore-Boston-Washington (Hb LBW, HBD: c.265 C > c.315 + 7 C) observed in 46 carriers (79.0%). Hb Lepore-Hollandia (HBD: c.69 A > c.92 + 16 A) was found in nine cases (16.0%); Hb Lepore-Baltimore (HBD: c.208 G > c.254 C) in two cases (4.0%) and Hb Lepore-ARUP (HBD: c.97 C > c.150 C) in one carrier (2.0%). Analysis of the hematological findings showed no significant differences between the four groups. The wide range of Hb Lepore variants observed in this study confirms the very diverse range of α- and ß-globin gene mutations observed in the UK population by previous studies.