The Prevalence and Role of Hemoglobin Variants in Biometric Screening of a Multiethnic Population: One Large Health System's Experience

Objectives: To characterize and quantitate hemoglobin (Hb) variantsdiscovered during biometric hemoglobin A1c (HbA1c) analyses ina large multiethnic population with a focus on the effect ofvariants on testing method and results. Methods: In total, 13,913 individuals had their HbA1c measured via ion-exchange high-performance liquid chromatography. Samplesthat had a variant Hb detected or HbF fraction more than 25%underwent variant Hb characterization and confirmation by gelelectrophoresis. RBC indices were also evaluated for possibleconcomitant thalassemia. Results: Of the 13,913 individuals evaluated, 524 (3.77%) had an Hbvariant. The prevalence of each variant was as follows: HbS trait(n = 396, 2.85%), HbSS disease (n = 4, 0.03%), HbC trait (n = 85,0.61%), HbCC disease (n = 2, 0.01%), HbSC disease (n = 5,0.04%), HbE trait (n = 18, 0.13%), HbD or G trait (n = 9, 0.06%),HbS β-thalassemia + disease (n = 1, 0.01%), hereditarypersistence of HbF (n = 2, 0.01%), and HbMontgomery trait (n =1, 0.01%). Concomitant α-thalassemia was detected in 20(3.82%) of the 524 individuals with an Hb variant. Conclusions: This study represents one of the largest epidemiologicinvestigations into the prevalence of Hb variants in a NorthAmerican metropolitan, multiethnic workforce and theirdependents and reinforces the importance of method selectionin populations with Hb variants.