Very low @entity79 ( @entity79 ) is now considered as diagnostic of @entity170 . Moreover, many @entity1 who are osteopenic eventually develop @entity3604 . Hence, bone density testing has occupied center stage in the diagnosis and treatment of this disorder. In addition, over the last several years, @entity79 has been utilized as the phenotype of choice for defining heritable markers for @entity3604 . However, genetic studies in @entity1 have been limited to some degree by the tremendous heterogeneity among populations, as well as multiple genetic, heritable and environmental determinants of the @entity79 phenotype. Recent advances in technology have afforded investigators the opportunity to study acquisition and maintenance of @entity79 in small animals. Along with newer knockout and transgenic strategies, quantification of @entity19 bone mass has advanced our understanding of both the biologic and genetic determinants of bone density. In this review, we will examine the use of the @entity19 to map the heritable factors that regulate bone acquisition. We will also examine the role of newer technology to decompose the bone density phenotype into components that are amenable to genetic studies. This review will focus on three models: (1) healthy inbred (2) recombinant inbred, and (3) congenic strains of @entity19 . Progress in this area with these strains has been rapid, and a summary of several quantitative trait loci (QTLs) is provided. The future of the @entity19 as a tool to map the genes that define the @entity170 is extremely promising.

Defining the genetics of @entity170 : using the XXXX to understand @entity1 .

@entity1 :: ('9606', 'Species') :: ['women', 'humans'] @entity3604 :: ('MESH:D058866', 'Disease') :: ['osteoporotic fractures'] @entity19 :: ('10090', 'Species') :: ['mice', 'mouse'] @entity170 :: ('MESH:D010024', 'Disease') :: ['osteoporosis syndrome', 'osteoporosis'] @entity79 :: ('MESH:D001847', 'Disease') :: ['bone mineral density', 'BMD']
@entity19 :: (10090,Species) :: ['mouse']
