Following a proof of concept study in 2007 (17), two pioneer GWAS for BMD were published in 2008 (18,19), identifying five significant loci associated with BMD, four of them near genes already known or suspected to be involved in the pathophysiology of osteoporosis (RANKL, OPG, ESR1, LRP5). The gene discussed is LRP5; the disease is osteoporosis.