In this study, a new alpha globin gene mutation on the a2-globin gene is reported. This mutation resulted in a Lys > stop codon substitution at position 127 which was detected in four individuals (three males and one female). DNA sequencing revealed this mutation in unrelated persons in Khuzestan province, Southwestern Iran of Lor ethnicity. This mutation caused no severe hematological abnormalities in the carriers. From the nature of substituted residues in a2-globin, it is widely expected that this mutation leads to unstable and truncated protein and should be detected in couples at risk for ?-thalassemia.