The − 2548AA homozygous genotype of LEP carriers had an increased risk for the development of dyslipidemia and − 2548GA shows a protective effect on DM, the biological causes of this are unknown, however, it is known that overdominant models occur when individuals heterozygous for a locus show a higher biological efficacy than individuals homozygous for that same locus, where the most severe manifestation for the disease or health status is when a double dose is received, either normal homozygous or mutated homozygous. The gene discussed is LEP; the disease is diabetes mellitus.