Candidate variants at 6p21.33 and 6p22.1 and risk of non-small cell lung cancer in a Chinese population.

Chromosome 6p21.33, containing BAT3 and MSH5 genes, together with chromosome 6p22.1 were recently identified as susceptible regions for lung cancer in Caucasian populations. These findings interest us in assessing whether genetic variants in these regions also contribute to lung cancer risk in Chinese populations. We genotyped the most significant single nucleotide polymorphism (SNP) (rs9295740) reported in Caucasian populations at Chromosome 6p22.1 and one common potentially functional variant (rs2075789) located at exon 2 of MSH5 in a case-control study including 1009 histologically confirmed non-small cell lung cancer (NSCLC) cases and 1127 cancer-free controls in a Chinese population. We found that the distributions of genotypes of both SNPs between cases and controls were not significantly different (P = 0.624 for rs9295740 and P = 0.937 for rs2075789). Logistic regression analyses revealed neither of the two SNPs was significantly associated with altered risk of NSCLC in dominant or recessive genetic models. When we compared the combined variant genotypes (GA+AA) with the common homozygote GG, assuming a dominant genetic model, the adjusted ORs were 1.03 (95% CI = 0.86-1.25) for rs9295740 and 1.03 (95% CI = 0.85-1.25) for rs2075789. In addition, no significant associations were observed in subgroups stratified by age, gender, smoking status or histologic types. Our results indicate that the most significant SNP rs9295740 identified in Caucasians in 6p22.1 and the potentially functional SNP rs2075789 in 6p21.33, seem not applicable to Chinese populations as susceptible markers for lung cancer. Re-sequencing and fine-mapping this region, along with extensive functional evaluations, is required.