1. Bone and Mineral Research Unit, Department of Medicine, School of Medicine, Oregon Health and Science University, 3181 Southwest Sam Jackson Park Road, Portland, OR 97239, USA.
2. Department of Orthopaedics and Rehabilitation, School of Medicine, Oregon Health and Science University, 3181 Southwest Sam Jackson Park Road, Portland, OR 97239, USA.
3. Department of Behavioral Neuroscience, School of Medicine, Oregon Health and Science University, 3181 Southwest Sam Jackson Park Road, Portland, OR 97239, USA.
4. Veterans Affairs Medical Center, 3710 Southwest U.S. Veterans Hospital Road, Portland, OR 97207, USA.
5. Department of Genetics and Genomics, Roche Palo Alto, 3431 Hillview Avenue, Palo Alto, CA 94303, USA.