Recent progress in understanding the genetic susceptibility to osteoporosis

Osteoporosis is a skeletal disease characterized by low bone mineral densit y (BMD) and microarchitectural deterioration, which leads to impaired skele tal strength and increased susceptibility to fracture [Anonymous, 1993]. Os teoporosis and its associated fractures are a significant cause of morbidit y and mortality among older individuals. Over 10 million Americans alone ha ve osteoporosis [Melton, 1997]. More than 1.3 million suffer fractures annu ally because of osteoporosis [Melton, 1997] at an estimated cost of $13.8 b illion in 1995 [Ray et al., 1997]. A genetic contribution to osteoporosis and fracture is well documented, but the genes and allelic variants conferring osteoporotic risk are largely un defined. Major efforts are currently underway, however, to identify the spe cific genes and allelic variants predisposing to this disease. In this arti cle, we review the importance of genetic factors in osteoporosis and the re cent progress in understanding its molecular genetic basis.