IGHE and Alzheimer disease: This result agreed with Deichmann et al,[18] who had confirmed the association of R576 allele with atopy, however, it has also found increased total IgE concentrations in patients with R576 allele and this agreed with Hershey et al,[19] who had reported an association between R576 allele and increased IgE level in AD and with Rosa-Rosa et al,[11] Beghe et al,[20] and Hytonen et al.[21] It seems that R576 gene might play a role in both conferring susceptibility to and modulating severity of atopy and/or asthma.