de Graaff LC, Argente J, Veenma DC et al.
Erasmus Medical Center, Sophia Children’s Hospital, Rotterdam, The Netherlands.
Clin Endocrinol (Oxf) 2009;70:742–50.
Editor’s note: In this study, the authors sought to examine the incidence and nature of mutations in the genes encoding pituitary growth hormone (GH1) and GH-releasing hormone receptor (GHRHR) in a sample of white Dutch patients with isolated GH deficiency. Isolated GH deficiency was defined using the conventional threshold of peak GH <20 mU/L in response to an arginine or clonidine test, or a more conservative definition that included patients with peak GH levels <30 mU/L and serum insulin-like growth factor-1 (IGF-1) <–2 standard deviation scores (SDS), but with otherwise normal pituitary hormone levels.