RESUMO
Lung cancer is the most frequent cancer among men in many countries. It is the result of interactions between genetic and environmental factors, among which tobacco smoking is a key environmental factor. CHRNA5, Cholinergic Receptor, Neuronal Nicotinic, Alpha Polypeptide-5, was previously reported to be associated with lung cancer risk. To identify the genetic susceptibility and tobacco smoking that influence lung cancer risk in Han population, we performed a case-control study in 228 patients and 301 controls. These data were compared using the χ(2)-test, genetic model analysis, and haplotype analysis. rs495956, rs680244, rs601079, rs555018, 588765 and rs11637635 showed an increased risk of lung cancer in both allelic model and genetic mode analysis. The genotype G/A-A/A of rs11637635 was most strongly associated with a 2.17-fold increased risk of lung cancer in dominant model (p = 0.018). One SNP, rs684513, was associated with a 0.645-fold decreased risk (p = 0.033) in allelic model analysis. By haplotype association analysis, haplotype sequences CTTATCAAAGA and GA of CHRNA5 were found to be associated with a 2.03-fold and 1.91-fold increased lung cancer risk (p < 0.05). Our results, combined with those from previous studies, suggest that genetic variation in CHRNA5 may influence susceptibility to lung cancer among Han smokers.
RESUMO
OBJECTIVE: To investigate the genetic association between schizophrenia and polymorphism of D-amino acid-oxidase (DAAO) gene. METHODS: A total of 112 parent/offspring trios in which the proband met the Amerecan Classification and Diagnostic Criteria for Mental Disorders (Fourth Revised Edition) were included in this study. Correlation analysis between schizophrenia and DAAO gene polymorphism and haplotype relative risk analysis were conducetd by using PCR and SNP typing in all the nuclear families. RESULTS: The rs3918347 allele was correlated to schizophrenia (P = 0.014). Allele A was a protective factor (Z = -2.37) and allele G the hazard factor (Z = 2.37). The frequency of rs3918347 allele A was 0.41 and that of the allele G was 0.59. The rs3741775, rs3825251 and rs4964770 alleles were not associated with schizophrenia. Three haplotypes of C/G in the rs3825251-rs3918347, G/T in the rs3918347-rs4964770, C/G/T in the rs3825251-rs3918347-rs4964770 were associated with schizophrenia (P = 0.021, 0.036, and 0.028, with genotype frequencies of 0.33, 0.28, and 0.15, respectively). CONCLUSION: The nucleotide polymorphism of DAAO gene is associated with schizophrenia in Chinese population.