Rare Coexistence of Hemoglobin D-Iran and Hemoglobin S in a Case from Central India.

Abstract

The hemoglobin variant, Hb D-Iran (HBB:c.67G > C), is a rare structural hemoglobinopathy mainly reported from Iran and Pakistan, with only limited documentation in India. Although usually clinically silent in the heterozygous state, it may coexist with other variants and complicate chromatographic interpretation. A 40-year-old woman from Central India was found to have two abnormal peaks in the HbA₂ (43.5%) and HbS (43.4%) windows on CE-HPLC, prompting further investigation. ARMS-PCR verified the presence of heterozygous HbS (HBB:c.20A > T), and additional tests excluded HbE and Lepore disorders, while definitive characterization through Sanger sequencing identified both Hb D-Iran and HbS mutations. Maternal screening revealed heterozygous Hb D-Iran, and the patient herself remained clinically asymptomatic, receiving genetic counseling following diagnosis. This case represents the first known report from India documenting the coexistence of Hb D-Iran with HbS. It underscores the importance of molecular diagnostic methods in accurately differentiating uncommon hemoglobin variants that may resemble more common patterns on CE-HPLC, especially in genetically heterogeneous populations.