INTRODUCTIONHemoglobinopathies are genetic disorders characterized by qualitative or quantitative abnormalities in globin chain synthesis. This study focuses on Hemoglobin C (HbC) disease, a structural hemoglobinopathy with diverse clinical and hematological manifestations. HbC disease is particularly relevant in populations with high consanguinity rates, where its phenotypic expression and associated complications warrant further investigation.OBJECTIVEThe aim of this study is to describe the hematological profile of patients with HbC disease diagnosed at the Central Hematology Laboratory of Ibn Sina University Hospital over a two-year period.MATERIALS AND METHODSA retrospective, descriptive study was conducted on 37 cases of HbC disease identified between November 2022 and November 2024. The study population included AC heterozygotes, CC homozygotes, SC compound heterozygotes, and HbC/beta-thalassemia combinations. The hematological evaluation comprised complete blood counts, reticulocyte counts, blood smear analysis, and hemoglobin fraction quantification using high-performance liquid chromatography (HPLC).RESULTSThe study identified four distinct HbC phenotypes: heterozygous AC (HbAC), homozygous CC (HbCC), compound heterozygous SC (HbSC), and HbC/beta-thalassemia combinations. The SC phenotype was associated with the most severe hematological abnormalities, including significant hemolysis and anemia. Variations in red blood cell morphology and hemoglobin fractions were observed across phenotypes, with elevated fetal hemoglobin (Hb F) levels noted in HbSC patients.CONCLUSIONThis study highlights the phenotypic diversity of HbC disease in a Moroccan population, emphasizing the role of consanguinity and genetic background in disease expression. The findings underscore the importance of tailored diagnostic and management strategies to address the burden of hemoglobinopathies in high-consanguinity regions.