IL4-590*T and IL4-RP2*183 alleles were found to be significantly over transmitted only amongst moderate-severe offspring asthma (ratio 15/6 of transmitted/non-transmitted; McNemar χ2 3.857, p-value = 0.039 OR 2.500, 95% CI 0.970-6.443 and ratio 14/4 of transmitted/non-transmitted; McNemar χ2 5.556, p-value = 0.015 OR 3.500, 95% CI 1.152-10.663, respectively). This evidence concerns the gene IL4 and asthma.