Real-Time Quantitative Polymerase Chain Reaction for Apolipoprotein E genotyping

Abstract

Background : Apolipoprotein E (ApoE) is an important substance responsible for the lipoprotein metabolism and thetransportation of lipid and known to play an important role in the body's physiological and pathological processes. Recently,ApoE genotyping test has been applied to the field of diagnostic methods for predicting high risk of Alzheimer's disease,cardiovascular diseases, as well as new diseases such as immune regulation disorders. Therefore, a faster and more accurateApoE genotyping test is required for the prevention of related disease and the general public health.Methods : We evaluated 220 serum specimens using two kinds of assays: one-stop Real-Q ApoE genotyping (BioSewoom,Seoul, Korea) and Seeplex ApoE ACE genotyping (Seegene, Seoul, Korea). The results were finally confirmed using sequencingas the reference. Statistical analysis was performed for the concordance rates between each assay and sequencing and thesensitivity and specificity were calculated with their 95% confidence intervals.Results : Sequencing results of 220 DNA samples showed 1 case of E2/E2, 139 of E3/E3, 9 of E4/E4, 17 of E2/E3, 4 ofE2/E4, 50 of E3/E4. The concordance rate between One-step Real-Q ApoE genotyping and sequencing was 100% (220/220),and that between Seeplex ApoE ACE genotyping and sequencing was 99.5% (219/220). Both sensitivity and specificity of OnestepReal-Q ApoE genotyping for every genotypes was 100%. The sensitivities and specificities of Seeplex ApoE ACEgenotyping were almost 100%, with two exception: 99.3% sensitivity in E3/E3 and 99.5% specificity in E2/E2.Conclusions : The performances of One-step Real-Q ApoE genotyping and Seeplex ApoE ACE genotyping were comparableoverall. However, the former showed better sensitivity and specificity comparable with those of sequencing. Hence, One-stepApoE genotyping could be a faster and more accurate option for ApoE genotyping.