All these genes are of potential biological significance: mRNA expression of ACACA and CTGF in adipose tissue is regulated by caloric intake [67,68] and upregulation of CTGF was observed in subcutaneous adipose in a model of dietary induced obesity [106]; differential expression of CETP during weight loss and maintenance was recently reported [69]; and the products of S100A8 and S100A9 form the calprotectin complex, a biomarker of obesity, for which increased circulating levels are associated with abdominal obesity, and adipose and systemic tissue inflammation [107-109]. Here, S100A9 is linked to obesity due to melanocortin 4 receptor deficiency.