The main results are: (1) reassuring results for bone quality and body composition evaluated by both HR-pQCT (with similar densities and microarchitecture between PN patients and controls) and DXA (with BMC similar to controls); and (2) higher but normal PTH levels despite correct vitamin D levels, with lower but normal osteocalcin levels in PN patients as compared to controls. This evidence concerns the gene BGLAP and poikiloderma with neutropenia.