The population dynamics of hemoglobins A, A2, F and S in the context of the hemoglobinopathies HbS and alpha-thalassemia in Kenyan infants
Macharia AW, Uyoga S, Ndila C, Nyutu G, Makale J, Tendwa M, Nyatichi E, Ojal J, Atkinson S, Williams TN
Few studies have described the dynamics of haemoglobin production in African populations with a high prevalence of haemoglobinopathies. We have used the BioRad Variant ClassicTM HPLC method to document the production patterns of the common haemoglobin variants HbA, HbA2, HbF and HbS, stratified by a+thalassaemia genotype, among 15,301 infants recruited to a study on the Coast of Kenya. Notably, we confirm that HbA2 measurements determined using this instrument are unreliable in HbAS and HbSS subjects. Further, we showed that HbA2 exceeded 4.0%, a level consistent with the presence of a-thalassaemia, in 0.8% of infants of HbAA phenotype who participated in our study. a-thalassaemia, has not been widely reported in the East Africa region and, as such, this finding merits further study.