Abbreviations: AJ, Ashkenazi Jewish; MAF, minor allele frequency; SNP, single-nucleotide polymorphism; UTR, untranslated region. Bold underlined SNPs indicate common SNPs that have total MAF . 0.05 that were chosen for genotyping. n.a. indicates SNPs genotyped and thus are nonapplicable. *Position is based on National Center for Biotechnology Information human genome build 37 coordinates. †MAF from sequencing analysis for SIRT1 gene region in 16 AJ centenarians and 16 AJ controls. ‡MAF and P value from genotyping and association analysis of SIRT1 in 213 AJ centenarians and 169 AJ controls. §These were not chosen for further genotyping because of the unclear sequence reads caused by multiple deletions in the

coactivator 1a, and AMP-activated protein On the basis of these studies in model organisms, there has been much interest in determining the role of SIRT1 functions in healthy aging in humans. To date, polymor- SIRT1 phisms in have been associated with several disease-related phenotypes, including diabetes, body mass index, obesity, cholesterol metabolism, energy expenditure, glucose tolerance, and cardiovascular dis- ease.3

with either longevity or lipid profiles in an Ashkenazi Jewish (AJ) population. We began by performing SIRT1 comprehensive resequencing analysis of to iden- tify variants in the exons, exon-intron junctions, and 3.1 kb proximal promoter region of 16 centenarians and 16 controls. A total of 36 sequence variants in the SIRT1 gene were identified, among which 5 had not been previously reported (Table I).

We next selected 19 common single- nucleotide polymorphisms (SNPs) with total minor allele frequency greater than 0.05 in the initial 32

To further investigate the role of SIRT1 in healthy ag- SIRT1 ing, we searched for polymorphisms associated

slaudividnihsiweJizanekhsA382niselfiorpdipilhtiwsPNSgat1TRISfonoitaicossA.IIelbaT 856239sr07860753sr66387721sr353491241sr45879901srPNS *tsujdaPTTTGGG*tsujdaPCCACAA*tsujdaPCCCTTT*tsujdaPTTTCCC*tsujdaPCCACAAepytoneG 2307197126730375809201414392851591n 6180.04165.895.469.487.363.376180.02719.761.18364.976180.09.7265.296.665.491.369.576180.09.862.89365.775630.04169015.468.586.3627egraL )%(LDL 8302.04.465.04266.538.165.134550.04.085.266.235.16434131.08.5165.449.261.934.161.235300.01.461.643.162.232140.02.561.441.264.636.163.03egraL )%(LDH 3575.01.066.91.064.91.064.93575.01.011.064.9064.96443.02.066.91.065.9064.93300.01.068.9064.93575.01.066.91.064.91.064.9LDH )mn(ezis .msihpromylopeditoelcun-elgnis,PNS;loretselohcnietorpopilytisned-wol,C-LDL;loretselohcnietorpopilytisned-hgih,C-LDH:snoitaiverbbA ,)mn(ezisLDL,selcitrapLDL,)%(LDHllams,)%(LDHmuidem,)%(LDHegral,)%(LDLllams,)%(LDLmuidem,)%(LDLegral,)Ld/gm(C-LDL,)Ld/gm(C-LDH,)Ld/gm(sedirecylgirt,)Ld/gm(loretselohC .elbatsihtninwohsera)50.0,eulavtsujdaP(tnacfiingiserewtahtsretemarapehtylnotubPNShcaehtiwsisylananoitaicossarofderusaemerew)Ld/gm(nietorpopilytisned-wolyrev,)mn(ezisLDH .)50.0,P(snoitaicossatnacfiingissetacidnienilrednudloB

individuals (indicated as bold in Table I) and genotyped them in 213 AJ centenarians and 169 AJ controls. A centenarian is defined as a healthy individual aged 95 years or older living independently, and a control is defined as an individual without a family history of un- usual longevity; parents of controls survived to the age SIRT1 of 85 years or less. The association analysis of with longevity was performed using SNP & Variation suite version 7.6.11 (Golden helix). Basic allelic test, genotypic test, additive model test, dominant model test, and recessive model test were performed and statis- tical differences among groups were assessed by the Fisher exact test. No association was found between SIRT1 SNPs and longevity (Table I).

SIRT1 genotype and lipid profiles in the same 382 indi- viduals. Because 5 tagSNPs (rs10997854, rs142194353, rs12778366, rs35706870, and rs932658) could capture all the SNPs with minor allele frequency greater than 0.05 across the SIRT1 gene region (r2 $ 0.9), association analysis with lipid profiles was performed with those tagSNPs. The test was performed using the JMP geno- mics program (version 6; Cary, NC), and numeric vari- 6 ables were expressed as the mean standard deviation (SD) (Table II). To assess the effect of each genotype within the SNP and continuous variables of lipid param- eters, logistic regression with adjustment for age and gender for additivemodel was carried out. Theresults re- SIRT1 vealedthat 2 tagSNPs were associated with 3 lipid parameters (Table II). The C allele of rs10997854, which SIRT1 served as a tag for 8 SNPs across the gene region, showed association with large low-density lipoprotein (LDL) and large high-density lipoprotein (HDL) by an additive model after multiple testing correction P 5 P 5 ( 0.0365 and 0.0412, respectively). In addition, the CT genotype of rs142194353 showed association with large LDL and HDL size by an additive model after P 5 P 5 multiple testing correction ( 0.0035 and 0.0033, respectively). Other lipid parameters showed no signifi- cant correlation with these SIRT1 SNPs.

slaudividnihsiweJizanekhsA382niselfiorpdipilhtiwsPNSgat1TRISfonoitaicossA.IIelbaT

Taken together, our data suggest that common vari- SIRT1 ants in are associated with lipid profile but not longevity in this AJ cohort. Prior association studies SIRT1 examining the relationship between variants and longevity have been mixed, with only 3 of more than 9 independent studies detecting a significant link. SIRT1 This suggests that the role of common variants in human longevity is minor or population specific. SIRT1 Interestingly, our resequencing analysis of from 32 individuals identified 5 novel SNPs, which were rare in frequency (Table I). Four of these SNPs were only found in centenarians, suggesting a potential role of rare SIRT1 variant in longevity. Further studies will be required to address this possibility.

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

, AG

, and AG