Research has shown that elevated CCL2 [77,82,90,93,94,95,96], CCL5 [81,86,90,97,101], CCL7 [82,88,90,91,102,103], CCL8 [54,84,89,90,91], CCL11 [81,104], CCR2 [40,77,90,91,92], and CCR5 [54,78,90] levels can be found in the samples (circulating, adipose tissue or others) from subjects (rodents and/or humans) with diabetes and obesity; additionally, CCL3 [90,97,98,99], CCL4 [90,97,99,100], and CCL13 [106,107,108] levels are increased in subjects with obesity (Figure 2), but some results are contradictory or exhibit sex differences (Table 1 and Table 2). The gene discussed is CCR2; the disease is obesity due to melanocortin 4 receptor deficiency.