Osteoporosis is a disease of progressive bone loss, leading to a weak and fracture prone skeleton. Osteoporosis is primarily a genetic disorder of low bone strength; however, strength cannot be measured in human in vivo. As a result, much remains to be discovered regarding the genetic basis of variation in strength. Here, we propose an innovative genetic analysis of a comprehensive suite of bone strength traits using Diversity Outbred (DO) mice. We will map high-resolution quantitative trait loci (QTL) for a wide array of bone traits including biomechanics, morphology, trabecular and cortical microarchitecture, marrow adiposity, dynamic histomorphometry and biomechanics. We will also use an innovative F1 in vivo validation strategy that mimics the complex genetic environment of QTL discovery using existing mutant mice or mice generated using CRISPR/Cas9. We will validate the role of Rhobtb3 and Soat1 in the regulation of bone strength and related traits. These genes were identified as candidates for bone strength QTL in a pilot study of CC and DO mice. Additional genes identified in the DO will be selected validated using existing mutant mice or through the development of mutants using CRISPR/Cas9. Our novel and innovative approach to gene discovery and validation has the potential to significantly increase our understanding of the basic biological processes that underlie variation in bone strength and lead to the discovery of novel therapeutic targets for the prevention and treatment of bone fragility.

Public Health Relevance

Osteoporosis is a major public health burden. Current estimates indicate that 12 million people suffer from osteoporosis in the U.S. Bone strength is the ultimate predictor of osteoporotic fracture; however, little is known regarding its genetic basis. This research will identify genes that regulate bone strength, which may lead to the development of novel treatments for bone fragility.

Agency
National Institute of Health (NIH)
Institute
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
Type
Research Project (R01)
Project #
1R01AR068345-01A1
Application #
9100229
Study Section
Genetics of Health and Disease Study Section (GHD)
Program Officer
Chen, Faye H
Project Start
2016-04-01
Project End
2021-02-28
Budget Start
2016-04-01
Budget End
2017-02-28
Support Year
1
Fiscal Year
2016
Total Cost
Indirect Cost
Name
University of Virginia
Department
Public Health & Prev Medicine
Type
Schools of Medicine
DUNS #
065391526
City
Charlottesville
State
VA
Country
United States
Zip Code
22904
Baliga, Nitin S; Björkegren, Johan L M; Boeke, Jef D et al. (2017) The State of Systems Genetics in 2017. Cell Syst 4:7-15
Sabik, Olivia L; Medrano, Juan F; Farber, Charles R (2017) Genetic Dissection of a QTL Affecting Bone Geometry. G3 (Bethesda) 7:865-870
Sabik, Olivia L; Farber, Charles R (2017) Using GWAS to identify novel therapeutic targets for osteoporosis. Transl Res 181:15-26