A disintegrin and metalloproteinase 33 (ADAM33)‎ gene polymorphism association with asthma in Egyptian children

الملخص EN

A disintegrin and metalloproteinase-encoding gene (ADAM33), was recently identified as an asthma susceptibility gene.

ADAM33 protein is expressed in smooth muscle cells of bronchi and pulmonary fibroblasts, playing a major role in airway remodeling.

Earlier studies, have mostly confirmed a link between ADAM33 and asthma as well as bronchial hyper responsiveness.

This work studied a group of Egyptian asthmatic children for 3 ADAM33 single nucleotide polymorphisms (SNPs), previously identified as putative risk alleles : T1 G > A(rs2280091), T2 A > G(rs2280090), V4 G > C(rs2787094) using Polymerase Chain Reaction–restriction fragment length polymorphism (PCRRFLP) with emphasis on their relation to clinical (severity, smoking, family history, and atopic manifestations) and laboratory data (Ig Immunoglobulin E (Ig E) level and absolute eosinophilia) and pulmonary functions.

Sixty (3–12 years old) asthmatic children and 32 matched controls were recruited.

The genotype distribution for the SNPs showed no significant difference between the patients and the controls.

A higher frequency of the (AA) genotype of T1 polymorphism was found in controls (75 %) than in patients (41 %), while the (AG) variant was higher in cases (46.6 %) than in controls (21.9 %) but with no statistically significant difference.

Also the (GG) genotype was higher in cases (11.6 %) than in controls (3.1 %) but with no statistical significance.

The allelic frequencies of T1 showed a higher (A) allele in controls (85.93 %) than cases having a suspected or previous alternative cause for recurrent wheezing.

This study also excluded those patients receiving long term anti-asthma medications or those on systemic steroids at the time of sampling or within the previous 2 weeks.

An informed written consent was signed by parents of all children included in the study.