Additionally, a subgroup analysis based on ethnicity demonstrated associations in the African and South American populations (p-value <0.05) but the Asian population showed no correlation between HP gene polymorphisms and sickle cell disease severity (p-value >0.05).<h4>Conclusions</h4>This meta-analysis demonstrates a significant association between HP gene polymorphisms and increased severity of sickle cell disease, suggesting that the HP genotype may serve as a valuable predictive biomarker for clinical outcomes. This evidence concerns the gene HP and sickle cell disease.