Background: Bronchial asthma is one of the most common chronic inflammatory respiratory
disorders affecting many people all over the world. Objectives: -to study the association
between single nucleotide polymorphism in genes of TLR2 and TLR4 and the risk of
bronchial asthma. Methodology: This study was carried out on 40 patients suffering from
bronchial asthma and 20 healthy subjects as a control group during the period from May
2014 to March 2015.The patients were chosen from the Chest Department of Benha
University Hospital. Skin prick test (SPT) was done to assess atopic state. Blood samples
were taken for detection of TLR gene polymorphism by Polymerase chain reaction -
Restriction Fragment Length Polymorphism (PCR-RFLP). Results: Statistical data for the
genotypic frequencies in TLR2Arg753Gln revealed that the homozygous (GG) genotype has
increased frequency among the controls (80%) as compared to the asthmatic patients
(30%)The heterozygous (AG) genotype was more prevalent among the asthmatic patients (
62.5%) as compared to the controls (15%) with OR =9.4, 95% CI (2.4-37.7) and significant
P-value. Also, the homozygous mutant (AA) genotype has increased trend in the asthmatic
patients (7.5%) than in the control subjects (5%), with OR = 0. 6, 95% CI (0.1-6.7) and nonsignificant
P-value Statistical data for the genotypic frequencies in TLR4Asp299Glyrevealed
that the homozygous (AA) genotype has increased frequency among the controls (70%) as
compared to the asthmatics (20%) . The heterozygous (AG) genotype was more prevalent
among the asthmatic patients (65%) as compared to the controls (30%) with OR =4.3, 95%
CI (1.4-13.8) and significant P-value. Conclusion: The major allele in TLR 2&4
polymorphisms (GG genotype of TLR2 and AA genotype of TLR4) might be generally
associated with a protective effect against bronchial asthma.