However, as GH deficiency, hypogonadism and obesity display a mutual relationship, it may be difficult to discern which dysfunction is causal if any; thus, distinguishing between organic GH and gonadotropin deficiency and obesity is difficult or even impossible, and poses a major diagnostic problem in suspected hypopituitarism in general and in isolated deficiencies in particular. This evidence concerns the gene GH1 and obesity due to melanocortin 4 receptor deficiency.