H19 and gastric cancer: Using Power and Sample Size Calculation (PS, version 3.0, 2009, http://biostat.mc.vanderbilt.edu/twiki/bin/view/Main/PowerSampleSize), considering H19 rs217727 C > T and rs2839698 C > T mutant alleles in the control group, OR, GC samples, and control sample sizes, the power of our analysis (α=0.05) was 0.862 and 0.854 in 500 gastric cancer cases and 500 controls with adjusted OR = 1.48 and 1.52 for H19 rs217727 C > T and rs2839698 C > T, respectively.