A recent report exploring the maternal cytokine profiles that may act as risk factors contributing to neurodevelopmental disorders identified an altered cytokine profile during the second trimester in women who gave birth to a child later diagnosed with ASD.6 This cytokine profile showed elevated IFN-γ, IL-4 and IL-5 and was considered consistent with an allergic/asthma clinical phenotype in humans,75, 76, 77 suggesting that allergy/asthma exposure may be a factor that drives maternal immune activation and increased risk for ASD. This evidence concerns the gene IL5 and Allergy.