Asthma and allergy researchers have found dust mite allergens in umbilical cord blood of some infants whose mothers were positive for the allergen, whereas none of the newborns whose mothers were negative for the common dust mite allergen known as Der p 1 carried the allergen themselves. Early life exposure to dust mite allergen has been linked to childhood asthma risk. The finding that in-utero exposure occurs as well suggests mothers could reduce their children's asthma risk by limiting their own allergen exposure, Dr. Abdul Bahrainwala, assistant professor in Wayne State 's School of Medicine , and colleagues noted in the "Annals of Allergy, Asthma & Immunology."