Results from meta-analysis of −137 G>C and cancer risk.

GC: Gynecological cancer; NC: Nasopharyngeal carcinoma; GUC: Genitourinary system cancer; GIC: Gastrointestinal cancer; N: number of studies included; OR: odds ratio; Ph: p value for heterogeneity;*OR with statistical significance;astudies with more than 500 participants;bstudies with less than 500 participants;