Systems genetic analysis in Diversity Outbred mice informs human bone mineral density GWAS and identifies Qsox1 as a novel determinant of bone strength
Genome-wide association studies (GWASs) for osteoporotic traits have identified over 1000 associations; however, their impact has been limited by the difficulties of causal gene identification and a strict focus on bone mineral density (BMD). Here, we used Diversity Outbred (DO) mice to directly address these limitations by performing the first systems genetics analysis of over 50 complex skeletal phenotypes. We applied a network approach to cortical bone RNA-seq data to discover 46 genes likely to be causal for human BMD GWAS associations, including the novel genes SERTAD4 and GLT8D2. We also performed GWAS in the DO for a wide-range of bone traits and identify Qsox1 as a novel gene influencing cortical bone accrual and bone strength. Our results provide a new perspective on the genetics of osteoporosis and highlight the ability of the mouse to inform human genetics. Overall design: Here, we sequenced total RNA from 192 Diversity Outbred marrow-depleted left femurs.