We examined pleiotropic effects by identifying SNP associations across two pairs of related traits. One SNP near PON1 emerged as associated with both age at death and morbidity-free survival. Surprisingly, there were relatively few SNPs associated with both traits; prior work had suggested that longevity per se and healthy aging may share common genetic pathways [11,12]. However, morbidity-free survival was measured at age 65 years; it is possible that as our participants age, morbidity-free survival defined atIdentify novel biological pathways related to lifespan control. Genome-wide association studies (GWAS) also have the potential to direct investigators of human aging to the most promising candidate gene associations and biological pathways reported to regulate lifespan in animal models. Enhancing our understanding of the mechanisms responsible for aging may, in turn, identify directions for health promotion and disease prevention efforts in middle-aged and older adults so that older persons can enjoy more time in good health. These data generate hypotheses regarding novel biological pathways contributing to longevity and healthy aging and serve as a resource for replication of findings from other population-based samples. Our strategy of selecting SNPs in candidate genes and regions previously reported to be associated with longevity yielded interesting findings. For age at death, we identified SNPs in or near several genes, including KL, LEPR, PON1, SOD2, and WRN. Defects in the WRN gene are the cause of Werner Syndrome, an autosomal recessive disorder characterized by premature aging. A longitudinal study of aging Danish twins recently reported a possible association between a successful aging trait and 3 SNPs in the WRN gene [44]. We were unable to determine if our SNP (rs2725369) was in LD with the SNPs in the prior report because the SNPs were not included in HapMap. Mutations in the KL (Klotho) gene in the mouse lead to a syndrome resembling human aging [45-47]. There has been one report linking a functional variant of the KL gene to human longevity [15]. Thus, results from this GWAS may direct resources to the most relevant candidate genes and pathways for further investigation in humans.

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Competing interests: The authors declare that they have no competing interests. 

Authors' contributions: All authors made substantial contributions to conception and design or acquisition of phenotypic data. JMM, KL, EJB, CG, DK, DPK, JMM, MJP and RBD contributed to the analysis and interpretation of data. JMM, KL, EJB, DK, DPK and SS have been involved in drafting the manuscript or revising it critically for important intellectual content. All authors read and approved the final manuscript. 

Additional material: Additional file 1 - Candidate Gene List for FHS K Longevity and Aging Traits. Click here for file [http://www.biomedcentral.com/content/supplementary/-/-/-S/-S/-S/doc].