SNPs of PIK3CA (p.Glu707Lys) and KDR (p.Gln472His) were more frequent in gastric cancer patients than in healthy Japanese people (p < 2.2 × 10–16 and p = 0.001, respectively; Bonferroni-corrected significance level = 0.003) (Supplementary Table S1). Here, PIK3CA is linked to gastric cancer.