The observed differences in the profile of leptin concentration in the blood of obese people with type 2 diabetes, depending on the examined individuals’ gender, should be, on one hand, linked with a greater secretory function of the fat tissue in women in relation to leptin and adiponectin, while, on the other hand, with a different impact of sexual hormones on secreting the adipokine in question [29]. This evidence concerns the gene ADIPOQ and type 2 diabetes mellitus.