Relatively high genetic prediction levels of MICB (OR = 0.9984; 95% CI, 0.9979–0.9989; p = 1.04 × 10−9) and PDE4D (OR = 0.9980; 95% CI, 0.9972–0.9987; p = 1.89 × 10−7) were observed to reduce the risk of asthma in children. This evidence concerns the gene PDE4D and asthma.