Molecular and Clinical Spectrum of Hemoglobin D: An Experience at a    Tertiary Care Diagnostic Center

Objective: To determine the clinical and molecular pattern of Hemoglobin D in patients presenting at tertiary care hospital. Study Design: Cross-sectional study. Place and Duration of study: Department of Hematology, Armed Forces Institute of Pathology, Rawalpindi Pakistan, from Jul 2020 to Mar 2021. Methodology: An automated cell analyzer was used to determine the whole blood count and red cell indices. D-10 BIORAD HPLC was used for quantitative assessment of Hb A, Hb F, Hb D and Hb A2. Where D-10 BIORAD HPLC showed an abnormal Hb D, capillary electrophoresis was performed using Sebia Capillary 2 Flex Piercing. Chelex DNA Extraction method was used. Molecular analyses for the confirmation of homozygosity and heterozygosity were done using Polymerase Chain Reaction (PCR) amplification. The clinical symptoms of the patients such as anemia, jaundice, pallor, weakness, hepatomegaly and splenomegaly were also noted Results: Among 90 patients, Hemoglobin D trait was found in 78(80.4%) of the patients out of which HbD-Punjab was seen in 57(73%) and HbD-Iran was found in 21(27%). Compound Heterozygotes (HbD/β) was found in 17(17.5%) and Compound Homozygous HbD/D was found in 02 (2.1%). All HbD-Punjab and HbD-Iran traits patients were asymptomatic, and few clinical symptoms were found in Compound Heterozygotes (HbD/β) and Homozygous HbD/D. Conclusion: Collective clinical history records, full blood count and electrophoresis and molecular results allow for the conclusive detection of the variant of Hemoglobin D. More multicenter, organized and detailed studies with larger sample size are required to draw concrete conclusions.