METHODS: We assessed specific-IgE to milk, wheat and peanut as well as specific-IgG4 to milk proteins (alpha-lactalbumin, beta-lactoglobulin, bovine serum albumin, caseins), egg, wheat and peanut in sera from 26 Amish and 26 Hutterite children.
RESULTS: The number of sera with detectable IgE to milk (p<0.05) and levels of IgG4 to alpha-lactalbumin >1µg/mL (p<0.01) were lower in Amish than Hutterite children. There was a similar trend for IgG4 responses to beta-lactoglobulin, bovine serum albumin, caseins and egg, but not for wheat or peanut.
CONCLUSIONS: Despite many shared genetic and lifestyle features, milk IgE and IgG4 responses are significantly lower in Amish than Hutterite children. This finding is in keeping with an inverse relationship between levels of endotoxin exposure in early childhood and aeroallergen sensitization. The fact that the difference is evident for milk, but not wheat or peanut, suggests that dietary differences may also be relevant.