CLPTM1L polymorphism as a protective factor for lung cancer: a case-control study in southern Chinese population.

Variants of the cleft lip and palate trans-membrane 1 like (CLPTM1L) gene, located on chromosome 5p15.33, were previously determined to influence lung cancer susceptibility. Here, we performed a case-control study to examine the potential association of CLPTM1L single nucleotide polymorphisms (SNPs) with lung cancer in a Chinese Han population. We selected four SNPs in the CLPTM1L gene that were previously reported to be associated with lung cancer. Odds ratios (ORs) and 95 % confidence intervals (CIs) were calculated to estimate the strength of the relationship between each CLPTM1L SNP and lung cancer risk. Allelic model analysis revealed that the minor alleles of all four SNPs were significantly associated with decreased lung cancer risk. Similar significant results were detected using genetic model analysis. In addition, we observed a protective effect of haplotype "TT" in the CLPTM1L gene. Our results verified that certain CLPTM1L polymorphisms are protective factors against lung cancer in a southern Chinese Han population and may be potential diagnostic and molecular markers for lung cancer patients.

Genetic polymorphisms of the drug-metabolizing enzyme cytochrome P450 2A6 in a Tibetan Chinese population.

Detection of CYP2A6 variant alleles, and knowledge about their allelic frequency in Tibetan ethnic groups, is important to establish the clinical relevance of screening for these polymorphisms to optimize pharmacotherapy. We used DNA sequencing to investigate the promoter, exons and surrounding introns, and untranslated region of the CYP2A6 gene in 100 unrelated healthy Tibetan individuals. We also used SIFT and PolyPhen-2 to predict the protein function of the novel non-synonymous mutation in CYP2A6 coding regions. We found 33 different CYP2A6 polymorphisms in the Tibetan population, five of which were novel: -98T > G in promoter region, 1886C > A, 5640C > A, 5827G > T in intron and missense mutation 5011G > A in exon 7. We identified six CYP2A6 alleles (*1, *10, *11, *14, *15 and *18), with a wide frequency range from 1.00% to 86.50% in the population. We also detected six CYP2A6 genotypes, with a wide frequency range from 2.00% to 73.00%. Three of which (*1/*10, *1/*11 and *1/*18) lead to decreased enzyme activity. This study provided new information regarding CYP2A6genetic polymorphisms in Tibetan individuals, which will greatly facilitate studies on the relevance of pharmacogenetics for CYP2A6 with respect to disease risk and to the pharmacokinetics and pharmacodynamics of many drugs.

RTEL1 polymorphisms are associated with lung cancer risk in the Chinese Han population.

RTEL1 (regulator of telomere elongation helicase 1; OMIM 608833) gene polymorphisms were linked to lung cancer (LC) susceptibility in a cancer genome-wide association study (GWAS) Here, we assessed whether seven previously reported RTEL1 polymorphisms influenced LC risk in Han Chinese population. All study samples (554 LC cases and 696 cancer-free controls) were collected from the Affiliated Hospital of Xizang Minzu University in China. We assessed associations between SNPs and LC risk using various several genetic models (codominant, dominant, recessive, overdominant, and additive). Whereas rs2738780 showed a protective effect against LC (Odds ratio (OR) = 0.80 ;95% confidence interval (CI): 0.638 = 0.998; p = 0.048), rs7261546(OR = 4.16; 95% CI: 1.35-12.82; p = 0.007), rs6062299(OR=5.08; 95% CI: 1.43-18.10; p = 0.005) and rs3787098(OR = 5.10; 95% CI: 1.43-18.15; p = 0.004) were all associated with increased LC susceptibility (recessive model). Haplotype analysis suggested that ''CTC'' was associated with a 0.8-fold decrease in LC risk (OR = 0.80, 95% CI, 0.63-1.00; Pearson's p = 0.05). These findings suggest a potential association between RTEL1 polymorphisms and LC risk in a Chinese Han population.