GHRL and diabetes mellitus: Such possible contributing factors may be a depletion of the GI neuroendocrine cells and a destruction of the enteric nervous system.22–25 However, the enteric nervous system seems to be unaffected in FAP Val30Met26,27 and no improvement of the GI function has been shown after Ltx,28,29 although a normalization of the endocrine cell count was noted.30 In diabetes mellitus a down-regulation of ghrelin and its receptor is linked to GI dysfunction,31,32 and it would be of interest to study if this is also the case in FAP patients.