Genetic Studies of Responses of Bones to Mechanical Stresses

Progress has been reported in a continuing program of molecular genetic studies of the responses of bones to mechanical stresses. Prior studies in mice and humans had provided evidence that mechanical loading stimulates bone formation and that immobilization or loss of mechanical stimulation leads to decreasing bone formation and increasing bone loss. Other prior studies in humans and mice had demonstrated that bone anabolic response differs widely among individuals subjected to the same degree of mechanical loading. The initiation of the present studies was motivated by the conjecture that variations in bone anabolic response among individuals are attributable to differences in the transcription levels of genes; that is, they are genetically controlled.