|
Background and Objective bronchial asthma (asthma) is a complex multi-gene diseases have a genetic predisposition, was familial aggregation, it happened, the development of interaction is determined by the patient's genetic predisposition and environmental exposure. At home and abroad asthma has conducted a lot of research, a growing number of researchers dedicated to the study of the genetic etiology of the disease, so far there are a large number of studies attempting to probe the crowd with asthma susceptibility gene, hope that through asthma easy the sense gene determination to help people better understand the pathogenesis of asthma, and also to provide clues for finding effective asthma treatment program. ADAM 33 (A disintegrin andmetalloproteinase33) gene single nucleotide polymorphism (singlenucleotide polymorphisms, SNPs) is more of a hot topic of research in recent years. The ADAM33 protein originally found in the cell membrane is a membrane anchor metal proteolytic enzymes because they have a disintegrin domain and metalloproteinase domain two functional areas, which is called a disintegrin a metalloproteinase. DNA sequence polymorphisms single nucleotide polymorphism is caused by a mutation in the genome nucleotide level, including the conversion of a single base, reversed and a single base deletion and insertion. The 2002 Van Eerdewegh, 460 asthmatic families from the United States and the United Kingdom the genome-wide scan to determine that there is closely associated with asthma and airway hyperresponsiveness (airwayhyperresponsiveness, AHR) candidate genes in chromosome 20p13. They then analysis of the 23 genes in the region of 135 SNPs analysis, found that three genes of the 24 SNPs associated with asthma and AHR, of which 14 SNPs in the ADAM33 gene, and mainly related SNPs in the ADAM33 gene 3 'end, and therefore determine the ADAM33 gene is associated with asthma and A HR susceptibility genes. From the genetic point of view, the genetic racial specificity. Different races, with one SNP frequency distribution of different, and the impact of asthma are not the same. Many researchers a case-control analysis, haplotype analysis and pedigree transmission disequilibrium test (TDT) explore the ADAM33 gene SNPs and asthma susceptibility, disease severity, lung function, allergic physical aspects of the association, the results are not all the same, and not seen some sort of SNP loci in all races have been reported. The ADAM33 gene function and role is not fully understood, but it selectively expressed in stromal cells, its activity change inevitably lead to abnormalities of airway smooth muscle cells and fibroblasts, suggesting AHR and airway remodeling related. Human ADAM33 gene the internal total of 179 SNP loci, including 25 in the coding region (5 synonymous mutations, 20 nonsense mutation), the gene polymorphism associated with the Chinese Han population asthma reported less In this study, a case-control study in Chinese Han population of normal individuals and patients with asthma as the research object, using direct sequencing methods to explore the ADAM33 gene polymorphism correlation between asthma and Chinese Han population. Materials and methods according to the Chinese Society of Respiratory Diseases Branch asthma study group developed asthma diagnostic criteria in our clinic and inpatient department randomly collected 186 clinical diagnosis of asthma cases in peripheral blood as the outer periphery of the group with asthma, 150 cases of healthy blood as a normal control group. Asthma group male 95 and 91 women, with an average age of 47.78 years old; 71 patients with pulmonary function tests; 159 peripheral blood EOS elevated in 186 patients, and a history of allergic rhinitis. Control group, male 78, female 72, average age of 41.92 years. The inquiry and examination to confirm the healthy subjects without asthma like symptoms, such as sudden onset of asthma, breathing difficulties, or chronic cough. All subjects were informed consent. The two groups of subjects are Han Chinese population by comparing two groups of objects age, sex had no significant difference. Extracted from peripheral blood DNA for research object, direct sequencing ADAM33 gene was amplified by PCR two SNP sites (S2, T2). By the SPSS13.0 calculation, two sample mean comparison using t test, genetic HW equilibrium test based on the genetic formula, group alleles between allele χ2 test was used to compare between the different severity of the disease using non- parametric tests, analysis of variance was used to compare between lung function; univariate logistic regression analysis of SNPs and asthma relative risk, and the difference was statistically significant at P <0.05. 1 between asthma and control groups age using t test, t = 0.486, P value of 0.627, the results shown in Table 1, between the two groups age no statistically significant difference. X2 test used to compare between asthma and control groups, gender, X2 value of 0.028, P value of 0.866, results are shown in Table 2, no significant gender differences in between the two groups. T2 locus of ADAM33 gene CC, CT, TT genotype frequency in the distribution of the asthma group were 139,47,0. Hardy-weinberg equilibrium test formula X2 = (OC) 2 / C X2 value of 3.74, P values ??greater than 0.05, genotype distribution in accordance with Hardy-weinberg equilibrium. Similarly calculated S2 sites X2 value of 2.01, P value greater than 0.05, Hardy-weinberg equilibrium genotype distribution in line with the results shown in Table 3. In the control group were T2 S2 sites according to Hardy-weinberg equilibrium test formula X2 = (OC) 2 / C calculate the X2 value of 0.998 and 1.43, respectively, P values ??were greater than 0.05, the results are shown in Table 4, the genotype distribution also in line with the Hardy-weinberg equilibrium, and has a good balance of the two samples. 4, on the T2 sites and is not detected TT genotype Perhaps the main reason is the lack of sample volume. In the case and control groups, the frequency of allele T were 12.6% and 7.6%, respectively, are shown in Table 12, P = 0.026, X2 test are shown in Table 5; S2 sites, case and control groups, and other bits The frequency of the gene C were 24.8% and 16.3%, respectively, are shown in Table 12, X2 test, P = 0.021, Table 5. The genotypes of the two SNP sites in case group and control group difference was statistically significant, indicating that the T2, S2 sites SNPs and asthma susceptibility. 5, according to the severity of the disease in patients with asthma were divided into mild, moderate and severe three groups by the nonparametric test T2 locus Z value of -0.13, P = 0.897, see Table 6; S2 sites X2 value of 0.419, P = 0.811, Table 7. The results show that the T2, S2 locus polymorphisms with asthma severity was not statistically related. 6, by logistic regression to calculate the relative risk of the two points of single nucleotide polymorphisms asthma T2 sites OR = 1.867, P value of 0.027; S2 sites OR = 0.444, P = 0.024; The results are shown in Table 8, the two SNPs, can significantly increase the risk of asthma. 7, according to the peripheral blood of patients with routine testing and asked whether the history of the use of drugs, the patients were divided into the two groups EOS increased and EOS does not increase, X2 test analysis object genotypes T2 locus X2 = 2.316, P = 0.128; S2 position X2 = 4.404, P = 0.111; The results show that the two SNPs, genotypes and EOS change was not statistically associated single nucleotide polymorphism can not affect the EOS. Variance analysis calculated genotype composition and lung function indicators FEV1 real / pre, FEV1/FVC and FVC real / pre-associated P value of T2 sites were 0.432,0.546,0.538; S2 sites P values ??were 0.640,0.427,0.738 that point T2, S2 SNPs and lung function showed no significant correlation. Conclusion is detected ADAM33 gene T2, the S2 locus SNPs with the Chinese Han population bronchial asthma susceptibility, rare alleles can increase the risk of asthma with allergic constitution and lung function was not significantly associated sex. Future work will further expand the number of cases and select additional sites to explore the the ADAM33 gene single nucleotide polymorphism associated with bronchial asthma in Chinese Han population and the role in the pathogenesis of asthma.
|