The effect of HbE, a hemoglobin variant, on the determination of HbA1/HbA1c using 4 commercial kits based on cation-exchange resin, cation-exchange column chromatography and specific antibody techniques was studied. Fifty-eight normal and 63 HbE heterozygous subjects were tested for HbA1 and HbA1c using 4 commercial kits i.e. Eagles Diagnostics, Boehringer Mannehim (BM), Diastat and Ames DCA 2000. Analyses of the samples by the 4 kits were done within one week and samples were stored at 4 degrees C before analysis. The results showed that HbE affects the determination of glycosylated hemoglobin using cation-exchange based and not kits based on specific antibody techniques.