Combined effects of the genetic variants in the <i>PTEN</i>, <i>AKT1</i>, <i>MDM2</i> and <i>p53</i> genes on the risk of nasopharyngeal carcinoma.

Abbreviations: OR, odds ratio; CI, confidence interval. aχ2 test for the distribution of genotypes between patients and control subjects. bP values were calculated by multivariate logistic regression, adjusted for age, sex, smoking and drinking status, smoking level, and nationality. cχ2 test for the Ptrend value of genotypes between patients and control subjects. dLow-risk group, individuals carrying 0–2 risk genotypes; high-risk group, individuals carrying 3-4 risk genotypes. *P value remained significant after c°rrection for multiple comparisons (P = 0.048).