Aims: The Southeast Asian (SEA) deletion (−−SEA) represents the most common determinant causing α thalassaemia in Southeast Asian countries. The embryonic ζ-globin chain has been defined as a marker for the detection of this deletion in adults. The aim of this study was to develop an appropriate low-cost ELISA for ζ-globin chain detection as a routine screening test for (−−SEA) α thalassaemia deletion.
Methods: A sandwich ELISA system for ζ-globin chains was established with a pair of ζ-globin-specific monoclonal antibodies prepared in-house, and locally made products. Against a gap-PCR method that was taken as the standard, this assay was validated in a cohort study testing a total of 526 individuals comprising patients scheduled for haemoglobinopathy diagnostic analysis and normal individuals. Routine screening of the (−−SEA) deletion in 300 random student volunteers was conducted using the assay.
Results: While the cut-off point was set at a percentage positive value of 30, the sensitivity and specificity of this ELISA method were 100% and 99.24%, respectively. The mean intra-assay and inter-assay coefficients of variation among the different concentrations in the optimised ELISA conditions were 2.1–11.4% and 4.3–13.2%, respectively. Seventeen of the 300 volunteers sampled were determined by the ELISA to have the (−−SEA) deletion; these results were in 100% agreement with the gap-PCR results.
Conclusions: This study validates the ELISA method described here as a simple, rapid and cost-effective assay that is potentially adaptable for application in large-scale population screening for this prevalent disorder in SEA areas such as southern China.
Statistics from Altmetric.com
Competing interests: None declared.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.