HEMOGLOBIN-SHERWOOD-FOREST DETECTED BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY FOR HEMOGLOBIN A(1C)

Hb Sherwood Forest has been so far identified in only one patient in 1 977. This study describes the second detection of this hemoglobin vari ant by routine high performance liquid chromatography (HPLC) in a diab etic patient and ber healthy grand niece. In both, glycosylated hemogl obin (HbA(1c) values were excessively elevated (52%), as determined by HPLC with a cation exchange column. The latex agglutination test show ed values of HbA,, in the expected normal range. Citrate agar electrop horesis revealed a hemoglobin variant with a mobility similar to HbF. Amino acid analysis and DNA sequence analysis revealed an Arg-->Thr ex change at codon 104 of the beta-chain. This sequence has been describe d as Hb Sherwood Forest in 1977. The hemoglobin variant is clinically silent and might be confused with excessively high HbA(1c) in routine measurement of glycosylated hemoglobin.