Abstract
Introduction
Beta-thalassemia is among the most common monogenic disorders in the Arabian Peninsula. This study aimed to investigate the β-globin (HBB) haplotypes among β-thalassemia patients in Saudi cohort which have potential implications in understanding the clinical care of patients and population genetic factors associated with β-thalassemia.
Methods
We analyzed 60 β-thalassemia patients. Male/female distribution for β-thalassemia was 58.33%/41.66%. Results of hematological parameters and indices were obtained from the database. HBB haplotyping assay was performed for four specific loci of the HBB gene cluster using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique.
Results
HBB haplotyping assay identified three novel patterns namely haplotype 1, haplotype 2, and haplotype 3 and three common African haplotypes including Benin, Senegal, and Cameron. The frequency of haplotype 1 was the highest among the studied samples (62%, n = 37) with 56.76% (n = 21) observed in males compared to 43.24% (n = 16) in females. This was followed by Senegal, haplotype 2, Benin and haplotype 3 with similar percentage, and Cameron haplotype with 18%, 12%, 3% and 2%, respectively. The relationship between these haplotypes and various hematological parameters was calculated and our study found no significant relationship (p-value >0.05).
Conclusion
Our study indicated the importance of finding out types of β-globin haplotypes as novel types being discovered. Though no statistically significant association was identified among all the haplotypes in terms of hematological parameters, Cameroon or Benin haplotypes had the mildest form because they have the highest means among all parameters. Further studies need to be carried out on a larger population to detect the frequency of each specific mutation in each haplotype among β-thalassemia patients. This would help to re-address the question of the origin(s) of the β-thalassemia.