β-Thalassemia pathogenic variants in a cohort of children from the East African coast
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
BACKGROUND: β-Thalassemia is rare in sub-Saharan Africa. Previous studies have suggested that it is limited to specific parts of West Africa. Based on hemoglobin A2 (HbA2 ) concentrations measured by HPLC, we recently speculated that β-thalassemia might also be present on the East African coast of Kenya. Here, we follow this up using molecular methods. METHODS: We used raised hemoglobin A2 (HbA2 ) values (> 4.0% of total Hb) to target all HbAA members of a cohort study in Kilifi, Kenya, for HBB sequencing for β-thalassemia (n = 99) together with a sample of HbAA subjects with lower HbA2 levels. Because HbA2 values are artifactually raised in subjects carrying sickle hemoglobin (HbS) we sequenced all participants with an HPLC pattern showing HbS without HbA (n = 116) and a sample with a pattern showing both HbA and HbS. RESULTS: Overall, we identified 83 carriers of four separate β-thalassemia pathogenic variants: three β0 -thalassemia [CD22 (GAA→TAA), initiation codon (ATG→ACG), and IVS1-3' end del 25bp] and one β+ -thalassemia pathogenic variants (IVS-I-110 (G→A)). We estimated the minimum allele frequency of all variants combined within the study population at 0.3%. CONCLUSIONS: β-Thalassemia is present in Kilifi, Kenya, an observation that has implications for the diagnosis and clinical care of children from the East Africa region.
Date Issued
2020-07-01
Date Acceptance
2020-04-11
Citation
Molecular Genetics and Genomic Medicine, 2020, 8 (7)
ISSN
2324-9269
Publisher
Wiley Open Access
Journal / Book Title
Molecular Genetics and Genomic Medicine
Volume
8
Issue
7
Copyright Statement
© 2020 The Authors. Molecular Genetics & Genomic Medicine published by Wiley Periodicals LLC. This is an open access article under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits use, distribution and reproduction in any medium, provided the original
work is properly cited.
work is properly cited.
Sponsor
Wellcome Trust
Wellcome Trust
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/32394645
Grant Number
091758/B/10/Z
202800/Z/16/Z
Subjects
Kenya
Thalassemia
hematology
hemoglobinopathy
Publication Status
Published
Coverage Spatial
United States
Article Number
e1294
Date Publish Online
2020-05-11