The A allele of -2548G/A polymorphism was found to be associated with higher leptin levels before lower BMI (body mass index) loss in women.24 The functional influence of the -2548G/A polymorphism on leptin expression stimulates great interest of many investigators to examine its association with breast cancers.25–31 However, only a few studies with inconsistent results have addressed the relationship between leptin and breast cancer.32–39 Liu and coworkers40 suggested that the A allele of -2548G/A polymorphism may be a determinant of cancer development. This evidence concerns the gene LEP and breast cancer.