Among premenopausal AA women, one SNP (rs425535) in chemokine (C-X-C motif) ligand 5 (CXCL5) was observed to be inversely associated with breast cancer risk (P-trend for the A allele= 0.006), with AG/AA genotypes associated with a 39% reduced risk compared to the GG genotype. This evidence concerns the gene CXCL5 and breast cancer.