Egypt J Pediatr Allergy Immunol, (October 2015), Volume No. 13, Issue 02  
Egypt J Pediatr Allergy Immunol 2015 ; 13 ( 02 ) : 49 - 55
, ESP - 195  
Original articles
Association of Polymorphism of two histamine-metabolizing enzymes with allergic asthma in Egyptian Children.
Dalia Shaalan   engy Osman   Dina Abdelhady   Noha Hazem      
Background: Histamine released from mast cells and basophils plays a key role in the development of allergic diseases such as allergic asthma, rhinitis or anaphylaxis. Histamine-metabolizing enzymes (N-methyltransferase and amiloride binding protein 1) are responsible for histamine degradation and involved in allergic inflammation. Objective: This study was undertaken to evaluate the relationship between polymorphisms of two genes encoding histamine metabolizing enzymes (HNMT and ABP1) with developing allergic asthma in Egyptian children. Methods: a case control study, that was performed on 100 atopic asthmatics patients& 94 healthy control children. Conventional method of PCR amplification was used for genotyping. Results: Distribution of HNMT -105 Thr → Ile (-314 C to T) SNP genotypes and Thr and Ile (C and T) alleles among patients and control revealed significant increase in Thr / Ile (CT) & Thr / Ile (CT) + Ile / Ile (TT) frequencies in atopic asthmatic patients than control (p 0.02&0.008 respectively). Also significant increase in Ile (T) alleles in atopic asthmatic patients than control (p 0.002). On the other hand 2029 CG SNP polymorphism of ABP1gene is significantly associated with atopic asthma (p=0.0003). Conclusion: the results obtained by this study suggest that genetic variation in the histamine-metabolizing enzymes (HNMT and ABP1) genes contributes to the pathogenesis of asthma in studied children.