Sickle cell disease patients with more severe genotypes (SS and Sβ0) had slightly greater levels of markers of endothelial function (TNF-α, IL-6, and IL-17A) than Sβ+ patients, but the difference was not statistically significant (p-values = 0.173, 0.583, and 0.720, respectively) (Fig. 2). This evidence concerns the gene IL6 and sickle cell disease.