All female and male patients had significantly higher median values of circulating CNTF than healthy subjects, with marked differences between the genders (Fig. 1B); in particular, unlike women with obesity with or without diabetes, whose CNTF levels were comparable, men with obesity and diabetes showed a higher median CNTF plasma concentration than men with obesity, even though the difference was not statistically significant. This evidence concerns the gene CNTF and obesity due to melanocortin 4 receptor deficiency.