The erythrocyte membrane properties of beta thalassaemia heterozygotes and their consequences for Plasmodium falciparum invasion

Malaria parasites such as Plasmodium falciparum have exerted formidable selective pressures on the human genome. Of the human genetic variants associated with malaria protection, beta thalassaemia (a haemoglobinopathy) was the earliest to be associated with malaria prevalence. However, the malaria protective properties of beta thalassaemic erythrocytes remain unclear. Here we studied the mechanics and surface protein expression of beta thalassaemia heterozygous erythrocytes, measured their susceptibility to P. falciparum invasion, and calculated the energy required for merozoites to invade them. We found invasion-relevant differences in beta thalassaemic cells versus matched controls, specifically: elevated membrane tension, reduced bending modulus, and higher levels of expression of the major invasion receptor basigin. However, these differences acted in opposition to each other with respect to their likely impact on invasion, and overall we did not observe beta thalassaemic cells to have lower P. falciparum invasion efficiency for any of the strains tested.

Spectrum of Genetic Mutation in Beta Globin Gene in Various Type of Thalassaemia in Bangladesh

Background: Hb-E/Beta thalassaemia is a congenital haemoglobin disorder which is a compound heterozygous state consists of qualitative disorder like Hb E variant & quantitative Hb disorder caused by genetic mutation of Beta chain. Objective: The aim of the study was to identify the beta gene mutation in Hb E/Beta thalassaemia. Method: A total of 32 diagnosed Hb E/Beta thalassaemia patients were included in this cross-sectional study from May 2019 to July 2020. Genetic analysis was done by sanger sequencing. Results: In this observational study, we found 13 different types of Beta gene mutations. Heterozygous for IVS 1-5(G>C) mutation was most frequent (53.1%). Conclusion: Genetic mutation is the confirmatory diagnosis for thalassaemia as well as one of the main factors for clinical expression. Mutation pattern also varies according to the geographical distribution. So, this study shows the frequently found mutation in Bangladesh and should carry out routinely to point out phenotypic expression.