Diversity of ß-Globin Haplotypes Associated with P-Thalassemia in Corsica (France)

In recent work the genetic structure of beta-thalassaemia diseases have been published and showed the particular incidence of the betadeg-39 mutation in Corsica. We report here the haplotype associations with this preponderant beta-thalassaemia mutation in 38 subjects that originating from centre Corsica. This analysis revealed an important genetic homogeneity with a preponderant association with haplotype II. It seems clear that this mutation has a unicentric origin. The presence of the betadeg-39 mutation could be explained by migration and founding effect. All the data support the hypothesis of West-Mediterranean origin for this mutation. This nearly exclusive association, with same the haplotype, also found in Sardinia, letting suppose that the inhabitants of the two islands were in contact with only one hearth thalassemic betadeg-39, and that maintains it of this change was supported by a founder effect and insularity, and with the endemic presence of malaria during many centuries. The knowledge of the frequency and distribution of beta-thalassaemia mutations in the Mediterranean population allows making at present time prenatal diagnosis of beta-thalassaemia on foetal DNA in the vast majority of the cases.