In view of our previous findings documenting a prominent role for ME1 in circulating leptin and insulin concentrations in obese male mice, and the emerging positive relationships between leptin and hyperinsulinemia with several human cancers, including those of the female breast and uterus [19,20,21,22], we herein extended our studies to female MOD-1 (C57BL/6N background) mice. The gene discussed is LEP; the disease is cancer.