The tumours of heterozygous carriers or homozygous carriers of the minor allele of SNP rs12443621, which is in strong linkage disequilibrium with SNPs rs8051542 and rs3803662 in the TNRC9 locus, were significantly more often negative for the progesterone receptor (41.4% and 52.3% for the heterozygous patients and for homozygous patients of the minor allele versus 38.2% in the homozygous patients for the major allele, P = 0.048). The gene discussed is TOX3; the disease is neoplasm.