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Summary A mutation in the LMNA gene is responsible for the most dramatic form of premature aging, Hutchinson–Gilford progeria syndrome (HGPS). Several recent studies have suggested that protein products of this gene might have a role in normal physiological cellular senescence. To explore further LMNA’s possible role in normal aging, we genotyped 16 SNPs over a span of 75.4 kb of the LMNA gene on a sample of long-lived individuals (LLI) (US Caucasians with age ‡ 95 years, N = 873) and genetically matched younger controls (N = 443). We tested all common nonredundant haplotypes (frequency ‡ 0.05) based on subgroups of these 16 SNPs for association with longevity. The most significant haplotype, based on four SNPs, remained significant after adjustment for multiple testing (OR = 1.56, P = 2.5 · 10 )5 , multiple-testing-adjusted P = 0.0045). To attempt to replicate these results, we genotyped 3448 subjects from four independent samples of LLI and control subjects from (i) the New England Centenarian Study (NECS) (N = 738), (ii) the Southern Italian Centenarian Study (SICS) (N = 905), (iii) France (N = 1103), and (iv) the Einstein Ashkenazi Longevity Study (N = 702). We replicated the association with the most significant haplotype from our initial analysis in the NECS sample (OR = 1.60, P = 0.0023), but not in the other three samples (P > 0.15). In a meta-analysis combining all five samples, the best haplotype remained significantly associated with longevity after adjustment for multiple testing in the initial and follow-up samples (OR = 1.18, P = 7.5 · 10 )4 , multiple-testing-adjusted P = 0.037). These results

We previously reported a genomewide linkage study for human longevity using 308 long-lived individuals (LLI) (centenarians or near-centenarians) in 137 sibships and identified statistically significant linkage within chromosome 4 near microsatellite D4S1564. This interval spans 12 million bp and contains ≈50 putative genes. To identify the specific gene and gene variants impacting lifespan, we performed a haplotype-based fine-mapping study of the interval. The resulting genetic association study identified a haplotype marker within microsomal transfer protein as a modifier of human lifespan. This same variant was tested in a second cohort of LLI from France, and although the association was not replicated, there was evidence for statistical distortion in the form of Hardy–Weinberg disequilibrium. Microsomal transfer protein has been identified as the rate-limiting step in lipoprotein synthesis and may affect longevity by subtly modulating this pathway. This study provides proof of concept for the feasibility of using the genomes of LLI to identify genes impacting longevity.