1. Department of Pediatric Dentistry, School of Dentistry, University of North Carolina-Chapel Hill, 228 Brauer Hall, CB#7450, NC 27599, USA
2. Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina-Chapel Hill, NC, USA
3. The Center for Observational Research, Amgen Inc., Thousand Oaks, CA, USA
4. Carolina Center for Genome Sciences, University of North Carolina-Chapel Hill, NC, USA
5. Department of Genetics, School of Medicine, University of North Carolina-Chapel Hill, NC, USA
6. Department of Biostatistics, Gillings School of Global Public Health, University of North Carolina-Chapel Hill, NC, USA
7. Lineberger Comprehensive Cancer Center, University of North Carolina-Chapel Hill, NC, USA
8. Department of Dental Ecology, School of Dentistry, University of North Carolina-Chapel Hill, NC, USA
9. Department of Periodontology, School of Dentistry, University of North Carolina-Chapel Hill, NC, USA