Sensitization to specific olive pollen-allergens (Ole e 2 and 10) has been correlated with a clinical pattern of asthma. This study analyzes the association between several polymorphims ofTNFA(G-308A,C-857T, andC-1031T),IL10(C-571AandA-1117G), andTGFB(C-509-T) and these sensitizations. These polymorphisms were genotyped by allelic discrimination, in olive pollen-allergic patients (phenotyped for specific Ole e 2 and 10 sensitizations) and healthy controls. Levels of serum-soluble cytokines were correlated with specific genotypes and clinical phenotypes. The results showed that heterozygousTGFB C-509Tgenotype, besides having the lowest sera TGF- levels, was significantly increased in olive pollen-allergic patients compared with controls. According specific sensitizations,CCgenotype ofIL10 C-571Acould be a protective factor for Ole e 2 sensitization and mainly for asthmatic Ole e 2 sensitized patients compared with asthmatic non-Ole e 2 sensitized patients (OR: 0.26,P=0.008). In contrast, heterozygousCAgenotype was increased in Ole e 2 asthmatic subjects compared to asthmatic non-Ole e 2 sensitized patients. Lastly, heterozygousTNFA G-308Agenotype was associated with Ole e 10 sensitization (OR: 2.5,P=0.04). In conclusion, these results suggest a role of TGF-β1 in olive-pollen sensitization and TNF-αand IL-10 genotypes in the asthma induced by specific olive-pollen allergens.