Additional factors involved in the pathogenesis of malnutrition are disorders of protein, carbohydrate, and lipid metabolism, oxidative stress, hormonal alterations (the action of thyroid hormone, growth hormone, and insulin), metabolic acidosis, and dialysis-related problems (increased protein breakdown as a consequence of the activation of certain metabolic pathways by the HD procedure itself). The gene discussed is GH1; the disease is malnutrition.