The role of TAP1 and TAP2 gene polymorphism in idiopathic bronchiectasis in children

Bronchiectasis is characterized by permanent changes in the structure and function of the airways. Its cause cannot be identified in some cases. A genetic disease can predispose to bronchiectasis in our country, where consanguinity of parents is common. Transporter associated with antigen presentation (TAP) deficiency syndrome is characterized by recurrent bacterial lower respiratory tract infections, which cause bronchiectasis. Our aim was to document the relationship between idiopathic bronchiectasis and TAP gene polymorphisms. Forty-four patients with idiopathic bronchiectasis and 100 healthy individuals as the control group were included. DNA was extracted and gene polymorphisms for TAP1 and TAP2 were studied. When compared to healthy controls, in the patient group, Ile/Ile genotype was decreased and Ile/Val genotype was increased in TAP1-333 polymorphism analysis; Asp/Asp and Gly/Gly genotypes were decreased and Asp/Gly frequency was increased in TAP1-637 polymorphism analysis; Ile/Val genotype was increased and Ile/Ile genotype was decreased in TAP2-379 polymorphism analysis; and Thr/Thr genotype frequency was decreased and Thr/Ala and Ala/Ala genotypes were increased in TAP2-665 polymorphism analysis. No statistically significant difference between patient and control groups was noted only in TAP2-565 polymorphism analysis. These results indicate that TAP gene polymorphisms may have had a role in the development of bronchiectasis in our patient group. Therefore, TAP deficiency syndrome should be considered in children with idiopathic diagnosis, since early diagnosis of the disease will improve life quality and survival.