The finding of a higher than normal frequency of the alternate C allele at SNP rs8570 position in the 3’UTR of RRAS2, the identification of somatic mutations at the SNP position, and the finding of gene amplification not only in breast tumor samples but also in blood, further support the idea that unmutated RRAS2 overexpression is the most important driver gene in human breast cancer. The gene discussed is RRAS2; the disease is breast cancer.