IL6R and obesity due to melanocortin 4 receptor deficiency: Of studies focused on IL-6R polymorphisms, some have analyzed females (in relation to IL-6 levels, CRP levels, bone mineral density, obesity, hyperandrogenism, preterm birth, type 2 diabetes, and melanoma) [25-32], and another concentrated on males (studying the relationship between IL-6R polymorphisms and obesity) [33].