Ten Years of Routine α- and β-Globin Gene Sequencing in UK Hemoglobinopathy Referrals Reveals 60 Novel Mutations.

We review and report here the genotypes and phenotypes of 60 novel thalassemia and abnormal hemoglobin (Hb) mutations discovered following the adoption of routine DNA sequencing of both α- and β-globin genes for all UK hemoglobinopathy samples referred for molecular investigation. This screening strategy over the last 10 years has revealed a total of 11 new β chain variants, 15 α chain variants, 19 β-thalassemia (β-thal) mutations and 15 α(+)-thalassemia (α(+)-thal) mutations. The large number of new thalassemia alleles confirms the wide racial heterogeneity of mutations in the UK immigrant population.

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 β-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.

Prenatal diagnosis of hemoglobinopathies by pyrosequencing: a more sensitive and rapid approach to fetal genotyping.

Prenatal diagnosis of the hemoglobinopathies by fetal DNA analysis is currently performed in most countries, either by DNA sequencing, restriction enzyme polymerase chain reaction (RE-PCR) or the amplification refractory mutation system (ARMS). These methods are time consuming and prolong the turnaround time for diagnosis. We here describe a method utilizing pyrosequencing for the prenatal diagnosis of 12 common nondeletional α- and β-globin gene mutations in the UK population.

Ten novel mutations in the erythroid transcription factor KLF1 gene associated with increased fetal hemoglobin levels in adults.

We investigated whether mutations in the KLF1 gene are associated with increased Hb F levels in ethnically diverse patients referred to our laboratory for hemoglobinopathy investigation. Functionally effective KLF1 mutations were identified in 11 out of 131 adult samples with an elevated Hb F level (1.5-25.

Characterization of a novel deletion causing beta-thalassemia major in an Afghan family.

We have identified and characterized a novel beta-globin gene deletion mutation in a family of Afghan ancestry. The proband was a 10-year-old transfusion-dependent female with the phenotype of beta-thalassemia major (beta-TM). DNA sequencing of the beta-globin gene showed no abnormalities.

Multiplex ligation-dependent probe amplification identification of 17 different beta-globin gene deletions (including four novel mutations) in the UK population.

Large deletions of the beta-globin gene cluster are problematic to diagnose, and consequently the frequency and range of these mutations in the UK is unknown. Here we present a study evaluating the efficacy of the recently available technique of multiplex ligation-dependent prob amplification (MLPA) to determine the range and frequency of these deletions in the UK population. The results revealed a large deletion mutation in 75 of 316 patient samples collected over a 3-year period.