Beta-globin gene haplotype in Hb SC disease

Area of Science:

• Hematology
• Genetics
• Molecular Biology

Background:

• Sickle cell disease (SCD) encompasses several genotypes, including sickle cell hemoglobin C (Hb SC) disease, a common variant.
• Genetic factors, such as specific beta-globin gene cluster haplotypes, are known to modify disease severity in sickle cell anemia.
• The role of these haplotypes in modulating hematological characteristics in Hb SC disease remains less understood.

Purpose of the Study:

• To investigate the association between different beta-globin gene cluster haplotypes and hematological parameters in adult patients with Hb SC disease.
• To determine if specific haplotypes correlate with varying levels of fetal hemoglobin (HbF) in individuals with Hb SC disease.

Main Methods:

• Genotyping of 73 adult patients diagnosed with Hb SC disease to identify the beta-globin gene cluster haplotype (Benin, Bantu/CAR, Senegal, atypical).
• Analysis of standard hematological parameters, including red blood cell indices and fetal hemoglobin levels.
• Statistical comparison of hematological data across different identified haplotypes.

Main Results:

• The Benin haplotype was the most prevalent (56%), followed by Bantu/CAR (25%), atypical (12%), and Senegal (6%).
• No statistically significant differences were observed in hematological characteristics or fetal hemoglobin levels among patients with Benin/C, CAR/C, Senegal/C, and atypical/C haplotypes.
• Fetal hemoglobin levels in this cohort of Hb SC disease patients were generally lower than typically reported for sickle cell anemia.

Conclusions:

• Beta-globin gene cluster haplotypes do not appear to significantly influence hematological features or fetal hemoglobin levels in patients with Hb SC disease.
• The lack of haplotype modulation suggests that genetic background may play a limited role in determining clinical variability within Hb SC disease, unlike in sickle cell anemia.