RARRES2 and obesity due to melanocortin 4 receptor deficiency: Because ob/ob mice are a standard model for the study of leptin effects or of monogenic obesity, other research groups have published different results on the measurement of the mRNA expression, where chemerin expression in wild-type and ob/ob mice is similar, but these mutant mice show an increase in the expression of CMKLR1; these findings indicate divergence in the regulation of the expression of chemerin and its receptor [36].