Identification of Hb Constant Spring: Using a PCR based technique

Abstract

Since Hb Constant Spring is the major cause of Hb H disease in SEA, accurate detection of high risk couples carrying the Hb Constant Spring genes will help genetic counseling and prenatal diagnosis. Hb CS-Hb H disease is associated with a more severe clinical state than Hb-H-deletional Hb H disease. We utilised a non radioactive method based on polymerase Chain Reaction to detect the Hb Constant Spring allele in normal and Hb H Constant Spring samples. The procedure involved 2 pairs of primer, namely A7 + A1B and ¶G2 +¶G4 to amplify the 314 and 191bp fragments from the normal and the Hb Constant Spring determinants respectively. Amplification was successfully done giving the 191bp fragment from the Hb Constant Spring allele and 314bp fragment from normal sample. We conclude that this procedure can be easily established as a screening test in the laboratory for detection of Hb Constant Spring genes.