Specifically, the IL4-590*CT/TT genotypes were significantly more frequent in asthma patients (35.8% vs. 20.0%, χ2 p-value = 0.009; OR 2.222, 95% CI 1.191-4.146), persistent asthma (37.8% vs. 20.0%; χ2 p-value = 0.006; OR 2.433, 95% CI 1.264-4.717), and moderate-severe asthma vs. the reference set (20% vs. 50.0%; χ2 p-value = 0.002; OR 4.000, 95% CI 1.701-9.434). This evidence concerns the gene IL4 and asthma.