Author Contributions: Dr Doria had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: Doria, Gervino, Hauser, Johnstone, Warram.
Acquisition of data: Doria, Wojcik, Xu, Gervino, Hauser, Johnstone, Nolan, Warram.
Analysis and interpretation of data: Doria, Wojcik, Xu, Gervino, Hauser, Hu, Warram.
Drafting of the manuscript: Doria, Wojcik, Xu, Hauser, Hu, Warram.
Critical revision of the manuscript for important intellectual content: Doria, Wojcik, Hauser, Johnstone, Hu, Gervino, Nolan, Warram.
Statistical analysis: Doria, Hu, Warram.
Obtained funding: Doria, Hu.
Administrative, technical, or material support: Doria, Wojcik, Xu, Nolan, Johnstone, Warram.
Study supervision: Doria, Gervino, Hauser, Warram.
Financial Disclosures: None reported.
Funding/Support:This study was supported by National Institutes of Health grants HL73168, HL71981, and DK36836 (Genetics Core of the Diabetes and Endocrinology Research Center at the Joslin Diabetes Center), and a grant from the Donald W. Reynolds Foundation.
Role of the Sponsors: None of the funding agencies had any role in the design and conduct of the study, in the collection, management, analysis, and interpretation of the data, or in the preparation, review, or approval of the manuscript.
Additional Contributions: We are grateful to Vincenzo Trischitta, MD, University of Rome, Rome, Italy; and Andrzej S. Krolewski, MD, PhD, Joslin Diabetes Center, Boston, for their valuable comments, and to Richard W. Nesto, MD, Lahey Clinic, Burlington, Massachusetts, for his initial help with the recruitment of study participants. The aforementioned individuals did not receive compensation for their contributions to this article. We are also grateful to the following employees of the Joslin Diabetes Center for their technical help: Christine Powers, BS, Ryan Thompson, BS, Maya Becker, BA, Aviva Bashan, BA, Jill Duffy, BS, Helen Kim, BS, Rachel Sagor, BA, and Celeste Amundsen, BA. We acknowledge the invaluable contribution by the individuals who participated in this study.