Abstract
An epidemiological molecular study was carried out to evaluate the spectrum and allelic frequency of α-thalassemia (α-thal) defects in Algeria. A series of 153 randomly selected blood donors was screened for 10 α-thal alleles described in the Mediterranean area. In addition, six unrelated cases with hematological and biochemical data suggestive of Hb H disease were investigated. Our data revealed an allele frequency of 4.6%. The presence of α0-thal determinants (−α20.5 and – –MED I) was observed both in Hb H patients and in the randomly collected samples. Overall, the −α3.7 deletion was the most prevalent allele (2.9%), followed by the αNco Iα (HBA2:c.1A>G) allele (0.6%) and by the αHph Iα (HBA2:c.95 + 2_95 + 6delTGAGG), −α20.5, – –MED I alleles (0.3% each). The −α4.2 deletion was observed in only one Hb H patient. These results outline the heterogeneity of the α-thal alleles in Algeria which reflects the anthropological history of the country. Because of their frequency, α-thal alleles are probably frequent modulators of prevalent β-globin gene-related hemoglobinopathies in Algeria.