Moreover, studies of post-TBI neuroendocrine dysfunction have found that the somatotropic axis (GH and IGF-I) seems to be the most commonly disrupted pituitary hormonal axis, in similarity to prolactin hormone disruption, whereas the thyrotrophic, corticotrophic, and gonadotrophic axes are less-affected (130), suggesting that GHD is linked to anemia. This evidence concerns the gene GH1 and anemia (phenotype).