MMP9 and breast cancer: The frequencies of the three MMP9 genotypes in controls were 50% (C/C), 33.7% (C/T) and 16.3% (T/T) while, in BC patients were 40.3% (C/C), 35.7% (C/T) and 24% (T/T), deviated from those expected from the Hardy Weinberg equilibrium (p<0.01).