Tehran University of Medical Sciences International Journal of Hematology-Oncology and Stem Cell Research 2008-2207 18 2 2024 04 16 183 191 Aya Ahmad Department of Pharmacy, Al-Sham Private University, AL-Tall Damascus, Syria Karram Fattoum Department of Pharmacy, Al-Sham Private University, AL-Tall Damascus, Syria Wael Imam Department of Pharmacy, Al-Sham Private University, AL-Tall Damascus, Syria MHD Yasser Mukhalalaty National Center for Thalassemia and Genetic Counseling, Damascus, Syria Musab Murad Department of Pharmacy, Al-Sham Private University, AL-Tall Damascus, Syria Faizeh Al Quobaili Department of Pharmacy, Al-Sham Private University, AL-Tall Damascus, Syria 2022 05 24 2023 09 20 Background: Hemoglobinopathies are common inherited blood disorders in our Mediterranean area. The main structural hemoglobin variants are hemoglobin S and hemoglobin C, due to their prevalence. We conducted this retrospective study to investigate and characterize hemoglobin C patients referred to the National Center for Thalassemia and Genetic Counseling and the management of hemoglobin C disease in Damascus. Materials and Methods: The study included patients referred to the National Center for Thalassemia and Genetic Counseling in Damascus between 2000 and 2022 for hemoglobin C detection. Gender, age, geographical origin, hemoglobin electrophoresis profile, and blood transfusion were considered for hemoglobin C patient classification. Blood transfusion in five consecutive years and linear regression with hemoglobin S and C values were determined. Results: 30 (14 males and 16 females) out of 624 patients between 3 and 46 years old (mean ± SD: 17.3 ± 9.7 years) showed hemoglobin C disease. Only eight patients (one male and seven females) received blood transfusions, and the remaining patients (13 males and 9 females) did not receive any transfusion. Only one patient with 100% hemoglobin C was detected; 19 showed HbSC, and 10 had HbAC. There was a significant correlation between hemoglobin S and geographical origin (P-value=0). Conclusion: A Homozygote hemoglobin C patient has mild hemolytic anemia, whereas the hemoglobin C 100% patient has only a one-time blood transfusion (he was 17 years old) in our study. The inherited combination of hemoglobin C and S is less severe than hemoglobin S alone. There is a significant relationship between hemoglobin S and geographical origin (p-value=0). https://ijhoscr.tums.ac.ir/index.php/ijhoscr/article/view/1847 https://ijhoscr.tums.ac.ir/index.php/ijhoscr/article/download/1847/1031