HBB, SER9TYR
A mutation where the serine in position 9 in the primary sequence of a beta-chain produced by the HBB gene is replaced by tyrosine. This mutation is one of 2 amino acid substitutions in the same beta chain that produces the asymptomatic Hemoglobin D-Agri, the other mutation being HBB, GLU121GLN, which on its own produces Hemoglobin D-Punjab.