CYP27B1 and cancer: After reading full-text, 21 articles were excluded, including 10 that did not describe GC (rs4588 and rs7041) or CYP27B1 (rs4646537, rs3782130) polymorphisms and cancer susceptibility, 2 that did not meet HWE, 4 case only or non-cancer subject only articles, and 5 that not provide detailed genotyping data.