VDR was the first candidate gene to be studied in relation to osteoporosis (Morrison et al., 1994; corrected in 1997), and most attention has focused on polymorphisms situated near the 3′ end of VDR that are recognized by the restriction enzymes BsmI, ApaI and TaqI (Ralston & de Crombrugghe, 2006). Here, VDR is linked to osteoporosis.