RESUMEN
Asthma is one of the most common chronic respiratory diseases, affecting â¼300 million children and adults worldwide. Previous studies identified a disintegrin and metalloprotease domain 33 (ADAM33) as an important susceptibility gene for asthma in patients of different nationalities; however, it is unknown whether this relationship exists in ethnically diverse populations. The present study focused on the association between single-nucleotide polymorphisms (SNPs) of the ADAM33 gene and asthma in the Uygur population of China. Three SNPs of ADAM33 (T1, S+1 and F+1) were genotyped in a case-control study among the Chinese Uygur population, involving 126 adult asthmatic patients and 126 healthy controls. The frequency of the ADAM33 T1 C allele among asthma patients was significantly higher compared to healthy controls (20.6 vs. 11.1%, P=0.003). The distribution of ADAM33 genotypes differed significantly between the two groups. The frequency of the T1 TC genotype was higher among patients compared to healthy controls [odds ratio (OR)=2.118, P=0.016] and the variant genotype, TC+CC, increased the risk of asthma (OR=2.244, P=0.005). Following adjustment for confounding factors, the ORs of TC and TC+CC for asthma were 2.317 and 2.522, respectively. There was a significant decrease in the forced expiratory volume (FEV1) levels in patients with the TC genotype compared to the TT genotype of T1. Haplotype analysis revealed that the frequencies of Hap5 (CAC) and Hap6 (CAT) were significantly higher among asthmatic patients compared to healthy controls (P=0.024 and 0.016, respectively). The genotype and allele frequencies of SNP S+1 and F+1 were not statistically different between asthmatic patients and controls. In conclusion, the ADAM33 T1 SNP may affect susceptibility to asthma in the Chinese Uygur population.
RESUMEN
OBJECTIVE: To analyze possible difference in bronchial asthma between ethnic and geographic groups and explore its correlates among Uygur and Han adults in Turpan Prefecture, Xinjiang. METHODS: One hundred and sixty-six clinically diagnosed asthmatic patients at Turpan Prefecture Hospital, Xinjiang, 86 of Uygur and 80 of Han ethnic, and 166 1:1 matched controls from ophthalmological outpatient department at the same hospital were recruited into the study. Interview with questionnaire was conducted and serum levels of eosinophilic cation protein (S-ECP), total IgE (T-IgE) and specific IgE (S-IgE) were measured for all of the participants to study related factors for asthma with univariate and multivariate conditional logistic regression analyses. RESULTS: Bronchial infection (OR(U) = 5.111, 95%CI: 1.203 - 21.710; OR(H) = 2.498, 95%CI: 1.471 - 5.069), family history of asthma (OR(U) = 3.078, 95%CI: 1.812 - 5.188; OR(H) = 2.711, 95%CI: 1.010 - 6.176), personal allergy history (OR(U) = 2.083, 95%CI: 1.043 - 4.162; OR(H) = 3.998, 95%CI: 1.739 - 9.198), weather change (OR(U) = 2.218, 95%CI: 1.199 - 3.778; OR(H) = 1.733, 95%CI: 1.004 - 2.994) and positive S-IgE (OR(U) = 1.592, 95%CI: 1.018 - 2.491; OR(H) = 3.858, 95%CI: 2.246 - 8.507) correlated with asthma in patients of both Uygur and Han ethnic. Percentage of asthma attack induced by respiratory infection [59.30% (51/86)] and weather change [36.05% (31/86)] in Uygur patients was significantly higher than that in Han ethnic [42.50% (34/80) and 21.25% (17/80), respectively], but percentage of those with personal allergy history [48.75% (39/80)] and positive S-IgE [52.50% (42/80)] in Han ethnic was significantly higher than that in Uygur [32.56% (28/86) and 30.23% (26/86), respectively]. Levels of S-ECP and T-IgE in patients with moderate and severe asthma of both Uygur and Han ethnic [(S-ECP(U) = 7.95 +/- 3.98) microg/L, S-ECP(H) = (11.21 +/- 4.74) microg/L, T- IgE(U) = (72.23 +/- 45.92) kU/L, T-IgE(H) = (108.81 +/- 64.07) kU/L, respectively]were significantly higher than those in controls of the same ethnic [S- ECP(U) = (1.94 +/- 1.16) microg/L, S-ECP(H) = (2.07 +/- 1.63) microg/L, T-IgE(U) = (46.19 +/- 32.47) kU/L, T-IgE(H) = (50.97 +/- 38.51) kU/L; t values were 8.96, 10.52, 2.81, 4.97, P < 0.01], higher in Han ethnic than those in Uygur (t values were 3.01, 2.68, P < 0.01). CONCLUSION: Bronchial infection, family asthma history, personal allergy history, weather change and positive S-IgE all were important correlates of asthma in Turpan Prefecture, Xinjiang. Levels of S-ECP and T-IgE in patients with moderate and severe asthma increased during its attacks, higher in Han ethnic than those in Uygur. Genetic and environmental factors may be involved in occurrence and development of asthma.
