The suppressor of cytokine signalling (Socs2−/−)-knockout mouse is characterised by an overgrowth phenotype due to enhanced GH signalling. The objective of this study was to define the Socs2−/− bone phenotype and determine whether GH promotes bone mass via IGF1-dependent mechanisms. Despite no elevation in systemic IGF1 levels, increased body weight in 4-week-old Socs2−/− mice following GH treatment was associated with increased cortical bone area (Ct.Ar) (P