Association Between GPRA Gene Polymorphism And Bronchial Asthma In Children

Bronchial asthma is a chronic inflammatory disorder of the airways which involves in many kinds of cells, particularly in mast cells and eosinophils.The disease is the most common chronic disease in childhood, and among asthmatic children, about 1/3 to 1/2 can prolong to adult.In recent decades, people around the globe suffer from asthma and this number is increassing . The latest investigation about asthma shows there are an estimated 150 million asthma patients world-wide and deaths from this condition have reached more than 180,000 annually.Estimates indicate a worldwide prevalence rate of asthma,from 0.11% to 0.32%. Those of developed countries are higher than the developing countries, and urban than rural.The incidence rate of adult asthma is 0.7% to 1.5%,and 0.11% to 2.03% in children. In the nation ,there are 1000 to 2000 million patients, and most of them are children and young adults.Because the characteristic of asthma are recurrent attacks and often severe attacks which can induce death without medical care timely, in addition, this chronic condition will affect normal studies, works and life of asthmatic subjects severely and brings heavy economic burden to families and society. So it is significant greatly to pay attention to the aetiology study of childhood asthma.Asthma is a disease of multifactorial inheritance originated by genetic and environmental factors , with heritability of 70% to 80%, heterogeneity and different genetic control mechanisms.The etiopathogenisis of asthma is very complicated. At present, mainly through genome scan, linkage analysis and candidate gene technology research,several genes associated with asthmahave been found. G protein-coupled receptor for Asthma susceptibility (GPRA) gene belongs to G protein-coupled receptors (GPCRs), and is related with asthma. GPRA gene, located on chromosome 7p15-p14 , has two major transcripts,GPRA-A and GPRA-B. GPRA gene may increase expression level of their transcripts in related tissue and GPRA-A can inhibit cell from growing potentially,which can play a certain role when asthma attacks.In this study, children were chosed,who suffering from bronchial asthma,and those of Han nationality in North China,without bronchial asthma,as subjects,and detected three SNPs of GPRA gene.Polymerase chain reaction and restriction fragment length polymorphism (PCR–RFLP)were adopted to examine individual genotype. Statistical software SPSS and Excel were used to handle the data on genotype.Goodness of fitχ2 test was used to detect whether SNPs distributions in the sample population were consistent with Hardy-Weinberg equilibrium. By comparing with the distributions in two groups, it can be determined that whether GPRA gene were associated with bronchial asthma.The study has screened three SNPs as follows: rs324960, rs324389 and rs 324383 of GPRA gene. There are comparability in age and sex between 118 cases of childhood asthma patients and 123 in healthy control group(P > 0.05). By the goodness of fit chi-square test,the distribution of genotype frequencies were consistent with the Hardy-Weinberg equilibrium, the two groups with group representation.The result is as follows: genotype frequencies of rs324960 site in both groups had no significant difference(χ~2=1.73,P>0.05),neither with allele frequency(χ~2=1.43,P>0.05), genotype frequencies of rs324960 site in both groups had no significant difference(χ~2=0.27,P>0.05),neither with allele frequency(χ~2=0.07,P>0.05), genotype frequencies of rs324960 site in both groups had no significant difference(χ~2=1.08,P>0.05),neither with allele frequency(χ~2=1.18,P>0.05),which suggested that there should be no association between GPRA gene and bronchial asthma in children.