No differences were obtained when expression levels for the different PPARs in nasal biopsies from healthy volunteers were compared with biopsies derived from patients with symptomatic allergic rhinitis (Figure 1): PPARα (mRNA in relation to 100,000 mRNA molecules of β-actin) 170 (53–4512) and 82 (43–491), PPARβδ 52 (14–481) and 43 (18–464) and PPARγ 305 (144–2628) and 321 (171–699) in controls and patients with rhinitis, respectively. This evidence concerns the gene ACTB and allergic rhinitis.