This work was funded by National Institutes of Health (NIH) grant AG

, AG

, and AG

All authors have read the journal’s authorship agree- ment.

In our study, lipid profiles have been determined by nuclear magnetic resonance–based subfractioned lipo- protein particle size. It is now well recognized that the cholesterol values from LDL-cholesterol or HDL- cholesterol do not accurately reflect the number of circulating LDL or HDL particles or metabolic syn- drome risk associated with them.4 Our study is the first to report the positive associations of subfractioned lipo- protein particle sizes with SIRT1 variants, suggesting a role of SIRT1 in modulating risk of metabolic syndrome in the AJ population.

We thank Dr Matt Kaeberlein of University of Wash- ington for the comments and editing of the manuscript.

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ACKNOWLEDGMENTS

Conflicts of Interest: All authors have read the jour- nal’s policy on disclosure of potential conflicts of inter- est. Authors have no financial disclosures to make and no conflicts of interest to disclose.