Osteoblasts and chondrocytes have receptors for GH, and addition of the hormone to these cells in vitro increases cell proliferation and differentiation.(1) Congenital GH deficiency in humans and laboratory animals results in decreased bone growth and osteopenia.(2,3) GH levels decrease with age, and GH deficiency may contribute to metabolic syndrome,(4) as well as to common metabolic bone diseases, including postmenopausal and senile osteoporosis.(5,6). The gene discussed is GH1; the disease is Osteopenia.