lymphotoxin-alpha gene polymorphism and asthma in Egyptian children

ABSTRACT

Tumor necrosis factor is a proinflammatory cytokine found in increased concentrations in asthmatic airways. The TNF-alpha [TNFA] and lymphotoxin-alpha [LTA] genes belong to the TNF gene superfamily located within the human major histocompatibility complex on chromosome 6p in a region repeatedly linked to asthma. In this study, we examined 30 asthmatic of average age +/- SD of 8.3 +/- 3.6 y and 28 non-asthmatic Egyptian children. We used the PCR-RFLP analysis to identify the polymorphism +252A>G in intron 1 in lymphotoxin-alpha gene. The frequency of the family history was more common [60%] than isolated asthmatic ones. Asthma was significantly more common in subjects with allele A of the LTA*Ncol polymorphism [55%], rather than allele G [45%]. The LTA*Ncol-A/A genotype [40%] was the preferable genotype to LTA*Ncol-G/A and LTA*Ncol-G/G genotypes. In addition, the severe persistent asthmatic cases were associated with the LTA*Ncol-AA genotype at a frequency of 80%, while the genotype LTA*Ncol-GG are associated with the mildest form of the disease. However, someone could predict the severity of asthma and hence the polymorphism of the LTA*Ncol. More than 93% asthmatic population lived in the randomized areas of Cairo where the air pollution. In conclusion, genotype frequencies for the LTA+252 polymorphisms were significantly different from controls. These findings may have implications for future early intervention studies by helping to identify infants at increased risk for wheezing and childhood asthma