Rapid PCR detection of the Hb constant spring mutation using an artificial-restriction fragment length polymorphism.

Hb Constant Spring (CS) is characterized by a mutation in the stop codon of the α2-globin gene (1). It is the most prevalent nondeletional α-thalassemia (tha1) and a major cause of Hb H disease in the Southern Chinese (2,3) and Southeast Asian (4) populations. Because of its instability and low levels in heterozygotes it cannot usually be detected by electrophoresis. Although several DNA-based diagnostic approaches have been developed (5–7), each of these methods is technically demanding. Herein we describe a simple method based on polymerase chain reaction (PCR) using a mismatched primer (8) and followed by electrophoretic analysis of artificial-restriction fragment length polymorphism (A-RFLP) to detect the Hb CS mutation.