Dkk-1 levels are higher in postmenopausal osteoporosis patients than in age-matched controls [13], and in osteoporosis patients higher Dkk-1 serum levels highly correlated with bone mass variables with inverse associations found between serum Dkk-1 expression and lumbar and femur T-score [52]; Dkk-1 expression in osteoblastic cultures from osteoporotic subjects is higher than in control cells [14]. Here, DKK1 is linked to osteoporosis.