We examined TGFB1 SNPs in relation to asthma risk and degree of atopy among 546 case-parent triads, consisting of asthmatics aged 4-17 years and their parents in Mexico City.
Combined analysis revealed that atopic asthmatic children co-inherited the risk alleles of TNF-alpha-308G/A and IL-13 +2044G/A more frequently than control children (aOR 1.91, 95% CI 1.00-3.65), and asthmatic children co-inheriting both risk alleles had significantly lower PC(20) values vs. asthmatic children homozygous for the common alleles (P=0.024).
The detection of statistical interaction models is one evidence of gene-gene interactions among Eotaxin genes, and this interaction is thought to influence the development of asthma.
An association between a specific TBX21 haplotype and allergic asthma in children is demonstrated for the first time and might explain previously detected associations between SNPs within TBX21 and asthma and bronchial hyperresponsiveness.
These results suggested that the variant might act as a functional genetic factor of bronchial asthma with a unique mechanism to upregulate local and systemic IL-13 concentration in vivo.
In order to examine whether polymorphisms in the candidate gene, TBX21, located on chromosome 17q21.32, are related to the risk of human asthma phenotypes, we have searched for genetic variations in the human TBX21 gene and identified 24 single nucleotide polymorphisms (SNPs), including five novel SNPs, by direct sequencing in Japanese subjects.
Cases showed significant higher frequency of the genotypes: IL-6-174 GG (P<0.05, OR=3.2, 95% CI=1.09-10) that was evident mainly in the uncontrolled asthma subgroup indicative of the possibility of being a severity genotype.
The following polymorphisms in ICAM1 were genotyped on 352 children with asthma and 270 controls: rs5491 (resulting in the amino-acid exchange K56M), rs5493 (G241S), rs5498 (K469E), rs5030400 (R478W) and rs885743 in the 3'-untranslated region.