IL 12B And IL 17A Gene Polymorphism Among Domestic Mites’ Sensitive Egyptian Allergic Patients

Abstract

Domestic mites have adapted to living in or around human dwellings. They belong to the family Pyroglyphidae in which Dermatophagoides farinae (D. farinae) and D. pteronyssinus are the most commonly encountered species. The term "storage mites" refers to mites from other families of Astigmata, frequently found in grains, hay, and straw. The growth and prevalence of mites may be affected by several factors, including temperature, humidity, and altitude. Domestic mites are the major source of allergens indoors. Allergy is caused by an interaction between environmental and genetic factors. Among populations; genes that predispose individuals to allergy are not consistent. In this regard, Th1 and Th2 interleukins and their gene polymorphism seem significant. These interleukins genes polymorphisms could affect the transcription of the genes, causing inter-individual variations in the production of cytokines. This work aimed to identify species of domestic mites in various Egyptian governorates and produce large amounts of domestic mites’ antigens by cultivation. It also aimed to evaluate of the role of single nucleotide polymorphisms of IL-12B (+1188A/C) and IL-17A (-197G/A) to confer susceptibility to domestic mites’ allergic diseases One hundred twenty dust samples were collected from allergic patients’ houses. Mites were isolated from the collected dust samples from six governorates in Egypt (Cairo, Menia, Menofia, Qalyubia, Sharqia, and Dakahlia) representing the four seasons and then mites were identified. Within 120 collected dust samples, six genera were identified: D. farina (69.4%), D. pteronyssinus (55.5%), Tyrophagus species (38.8%), Blomia tropicalis (30.5%), Cheyletus malaccensis (13.8%). Euroglyphus maynei (5.5%) and Tarsonemus species (5.5%). The highest positive domestic mites’ samples were in Qalyubia (73.7%) and the lowest positive samples were in Cairo (33.3%). The highest numbers of domestic mites populations were during spring and autumn.