Time estimations by network of beta globin gene cluster haplotypes linked with Hb D-Los Angeles [β121 (GH4) Glu → Gln GAA → CAA] mutation in the world populations

Abstract

Background: β-Globin gene cluster haplotypes associated with the Hb D-Los Angeles mutation have been reported in many different locations in different populations including Italy, Iran, Thailand, Belgium, Mexico, Holland, and Turkey. In this study, we have identified genetic relationships and formation periods between the haplotypes reported in the world regarding the Hb D-Los Angeles. Methods: We comparatively analyzed the RFLP (restriction fragment length polymorphism) data in Denizli region and world populations using Arlequin 3.5 statistical software program. The data obtained from the Arlequin software were then entered into the Phylogenetic Network software to calculate the age estimates and to discover possible links between the haplotypes. Results: We observed the frequencies of the β-globin gene haplotypes for the seven polymorphic restriction sites around the world and calculated the estimated time of haplotypes using Network software on the basis of ancestral haplotypes. We performed the phylogenetic network analysis of the haplotypes linked with Hb D-Los Angeles mutation by processing the data of frequency and age estimations with Network software. Conclusion: Our period of time results suggests that HAP1 was formed before modern human migration to Asia and/or independent origin of the Hb D-Los Angeles mutation from other populations. Considering that the population in Denizli region started the Hb D-Los Angeles mutation past about 40,000 years ago, it can be said that HAP1, HAP15, and HAP21 belong to the gene pool with an external effect. Our period of time results of HAP6 is compatible with published dating results.