Susceptibility to osteoporotic fracture is determined by allelic variation at the Sp1 site, rather than other polymorphic sites at the COL1A1 locus
Previous studies have identified an association between osteoporotic fracture and a polymorphism affecting a Sp1 binding site in the first intron of the collagen type I alpha 1 gene (COL1A1). It is currently unclear, however, whether this association is direct or the result of linkage disequilibrium with other polymorphisms situated nearby. In this study we analyzed the relationship between four w