SNP of CSN2 exon VII allele A2 (201-CCT-203, GenBank: JX273429.1) and allele A1 (201-CAT-203, GenBank: JX273430.1) [8] produces the substitution of proline 67 (Pro67) of BC A2 for histidine (His67) in BC A1 [9]. The gene discussed is CSN2; the disease is breast cancer.