Molecular Detection of Hemoglobin O-Arab in the Sudanese Population.

Background and Purpose: Sickle cell disease (SCD) is an inherited hemoglobin disease affecting the red cells and causing hemolytic anemia. It is a very common, endemic disease in Sudan, particularly in the central and western areas of Sudan. Sickle cell anemia (SCA) is when the patient has beta-globin gene variant (Hb S variant). In this study, we screened the co-inheritance of hemoglobin O-Arab mutation among Sudanese sickle cell disease patients. Study Population and Methods: This cross-sectional study was conducted in the Sudan-Khartoum state from November 2016 to December 2021. Blood samples were collected from a random sample of the known sickle cell disease patients of Kordofan-central Sudan origin. Study-appropriate blood samples were subjected to complete blood count (CBC), hemoglobin capillary electrophoresis (CE) and molecular laboratory investigations. Initial laboratory investigations were done in Sudan, where the DNA sequencing technique was carried out at the Egyptian National Research Center (NRC)-Cairo-Egypt. Results: The final study's main results revealed the presence of HB O-Arab genetic mutations among Sudanese Sickle cell disease patients, which estimated to be (5%) co-inherited mutations among our study population (Hb-O Arab; (HBB):c.364G>A (p.Glu122Lys)). Conclusion: The frequency of Hb-O Arab gene mutations was determined among Sudanese sickle cell disease patients, and the results have shown a (5%) frequency of Hb-O Arab mutation. The study result is the first molecular confirmation of co-inherited Hb-O Arab/sickle cell disease clinical condition in Sudan. The results raise the importance of extended studies of other sickle variant conditions.