PARP1 and cancer: The studies were further stratified on the basis of cancer type and the results showed that PARP-1 V762A polymorphism may be a risk factor of lung cancer in all of the genetic models except the heterozygous model (dominant model: OR = 1.16, 95% CI = 1.00–1.33; recessive model: OR = 1.32, 95% CI = 1.09–1.61; homozygous model  =  OR = 1.42, 95% CI: 1.14–1.76; heterozygous model  =  OR = 1.10, 95% CI = 0.95–1.28; allele model: dominant model: OR = 1.16, 95% CI = 1.05–1.28; Table 2; Figure 4).