Family history of allergies, classification of persistent and intermittent AR patients, comorbidities (conjunctivitis, pharyngitis, sinusitis, asthma, otitis media, obstructive sleep apnea) and sensitivity to D. pteronyssinus and B. tropicalis were also not showed significant differences with each gene expression (ZO-1, ZO-2, ZO-3, HDAC1 and HDAC2) of AR patients (Table 4). This evidence concerns the gene HDAC2 and allergic disease.