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Abstract
PURPOSE OF REVIEW The world population is aging and a rapid increase is being seen in the very elderly (aged >80 years). Cholesterol levels in general rise with age and high cholesterol has been associated with extreme longevity. The relationship between lipids and cardiovascular events in the extreme elderly is unclear. RECENT FINDINGS A number of genetic factors associated with lipid metabolism have also been described as having potential antiaging roles, including the genes encoding lipoprotein-associated factors - apolipoprotein E and cholesterol ester transfer protein; adipose tissue metabolism - adiponectin, leptin, glycaemia; and blood pressure - angiotensinogen. Clinical trials of lipid-lowering therapies have recruited subgroups of moderately elderly patients, but only the Prospective Study of Pravastatin in the Elderly at Risk (PROSPER) trial specifically recruited an elderly population. There is no direct equivalent of the Hypertension in the Very Elderly trial (HYVET) study of antihypertensive patients in the extreme elderly. No heterogeneity has been seen with the effects of statin therapy in the elderly compared with younger age groups on classical cardiovascular endpoints of coronary heart disease and stroke. SUMMARY The optimal cholesterol target, long-term tolerability and the specific effects of statins on other vascular-associated diseases of aging, for example arterial aneurysms, microvascular renal and cerebral disease (dementias), remain to be determined.
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Abstract
SummaryThis study examines local heterogeneity in the aptitude of Sardinian mothers towards late reproduction, and explores its temporal persistence and association with both post-reproductive longevity and propensity to consanguineous marriage. Data on women's fertility from 1961 and birth records for 1980–1996 from Vital Statistics were analysed by means of the following indicators: the incidence of old mothers at last childbirth, female mortality (1980–2001) at 80 years of age and over and the proportion of consanguineous marriages (1930–1969). A variable kernel-smoothing method was used to create interpretable representations of the true spatial structure of the indicators, and to highlight areas of higher than expected intensity. In particular, an area of reproductive and post-reproductive longevity was identified where the traits combine with a higher tendency to relatedness. Intriguingly, this area corresponds approximately to the geographically and historically well defined central-eastern zone, which was the refuge of Sardinians during past invasions, and overlaps the Ogliastra region, which has been widely studied for its genetic homogeneity.
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Poulain M, Pes G, Salaris L. A population where men live as long as women: villagrande strisaili, sardinia. J Aging Res 2011; 2011:153756. [PMID: 22132327 PMCID: PMC3205712 DOI: 10.4061/2011/153756] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Revised: 05/11/2011] [Accepted: 06/09/2011] [Indexed: 11/20/2022] Open
Abstract
Usually women live longer than men and female centenarians largely outnumber male centenarians. The findings of previous studies identifying a population with a femininity ratio close to 1.0 among centenarians in the mountainous region of Sardinia was the starting point of an in-depth investigation in order to compare mortality trajectories between men and women in that population. The exceptional survival of men compared to women emerges from the comparison with similar Italian data. Age exaggeration for men has been strictly excluded as a result of the age validation procedure. The discussion suggests that besides biological/genetic factors, the behavioral factors including life style, demographic behavior, family support, and community characteristics may play an important role. No single explanation is likely to account for such an exceptional situation and a fully integrated multidisciplinary approach is urgently needed.
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Affiliation(s)
- Michel Poulain
- FNRS, IACCHOS, Université Catholique de Louvain, 6000 Charleroi, Belgium
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Pal A, Srivastava T, Sharma MK, Mehndiratta M, Das P, Sinha S, Chattopadhyay P. Aberrant methylation and associated transcriptional mobilization of Alu elements contributes to genomic instability in hypoxia. J Cell Mol Med 2011; 14:2646-54. [PMID: 19508390 PMCID: PMC4373486 DOI: 10.1111/j.1582-4934.2009.00792.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Hypoxia is an integral part of tumorigenesis and contributes extensively to the neoplastic phenotype including drug resistance and genomic instability. It has also been reported that hypoxia results in global demethylation. Because a majority of the cytosine-phosphate-guanine (CpG) islands are found within the repeat elements of DNA, and are usually methylated under normoxic conditions, we suggested that retrotransposable Alu or short interspersed nuclear elements (SINEs) which show altered methylation and associated changes of gene expression during hypoxia, could be associated with genomic instability. U87MG glioblastoma cells were cultured in 0.1% O2 for 6 weeks and compared with cells cultured in 21% O2 for the same duration. Real-time PCR analysis showed a significant increase in SINE and reverse transcriptase coding long interspersed nuclear element (LINE) transcripts during hypoxia. Sequencing of bisulphite treated DNA as well as the Combined Bisulfite Restriction Analysis (COBRA) assay showed that the SINE loci studied underwent significant hypomethylation though there was patchy hypermethylation at a few sites. The inter-alu PCR profile of DNA from cells cultured under 6-week hypoxia, its 4-week revert back to normoxia and 6-week normoxia showed several changes in the band pattern indicating increased alu mediated genomic alteration. Our results show that aberrant methylation leading to increased transcription of SINE and reverse transcriptase associated LINE elements could lead to increased genomic instability in hypoxia. This might be a cause of genetic heterogeneity in tumours especially in variegated hypoxic environment and lead to a development of foci of more aggressive tumour cells.
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Affiliation(s)
- Arnab Pal
- Department of Biochemistry, All India Institute of Medical Sciences, New Delhi, India
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5
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Abstract
Alu PCR is a rapid and easy-to-perform "DNA fingerprinting" technique based on the simultaneous analysis of many genomic loci flanked by Alu repetitive elements, which allows the detection of genetic polymorphisms and mutations in human and primate genomes. In the protocol described in the present chapter, two fluorochrome-labelled primers complementary to Alu sequences are used to perform the PCR, and the amplification products are then analysed by capillary electrophoresis. The resulting -complex electrophoretic pattern may show sample-to-sample variability due to insertion, deletion, or sequence change of Alu retrotransposons, or caused by length variation of the sequence interposed between two Alus.
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Affiliation(s)
- Maurizio Cardelli
- Laboratory of Immuno-Oncology, Istituto Nazionale Riposo e Cura Anziani, Ancona, Italy.
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Cardelli M, Nicoli M, Bazzani A, Franceschi C. Application of Wavelet Packet Transform to detect genetic polymorphisms by the analysis of inter-Alu PCR patterns. BMC Bioinformatics 2010; 11:593. [PMID: 21143911 PMCID: PMC3012677 DOI: 10.1186/1471-2105-11-593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2009] [Accepted: 12/09/2010] [Indexed: 11/30/2022] Open
Abstract
Background The analysis of Inter-Alu PCR patterns obtained from human genomic DNA samples is a promising technique for a simultaneous analysis of many genomic loci flanked by Alu repetitive sequences in order to detect the presence of genetic polymorphisms. Inter-Alu PCR products may be separated and analyzed by capillary electrophoresis using an automatic sequencer that generates a complex pattern of peaks. We propose an algorithmic method based on the Haar-Walsh Wavelet Packet Transformation (WPT) for an efficient detection of fingerprint-type patterns generated by PCR-based methodologies. We have tested our algorithmic approach on inter-Alu patterns obtained from the genomic DNA of three couples of monozygotic twins, expecting that the inter-Alu patterns of each twins couple will show differences due to unavoidable experimental variability. On the contrary the differences among samples of different twins are supposed to originate from genetic variability. Our goal is to automatically detect regions in the inter-Alu pattern likely associated to the presence of genetic polymorphisms. Results We show that the WPT algorithm provides a reliable tool to identify sample to sample differences in complex peak patterns, reducing the possible errors and limits associated to a subjective evaluation. The redundant decomposition of the WPT algorithm allows for a procedure of best basis selection which maximizes the pattern differences at the lowest possible scale. Our analysis points out few classifying signal regions that could indicate the presence of possible genetic polymorphisms. Conclusions The WPT algorithm based on the Haar-Walsh wavelet is an efficient tool for a non-supervised pattern classification of inter-ALU signals provided by a genetic analyzer, even if it was not possible to estimate the power and false positive rate due to the lacking of a suitable data base. The identification of non-reproducible peaks is usually accomplished comparing different experimental replicates of each sample. Moreover, we remark that, albeit we developed and optimized an algorithm able to analyze patterns obtained through inter-Alu PCR, the method is theoretically applicable to whatever fingerprint-type pattern obtained analyzing anonymous DNA fragments through capillary electrophoresis, and it could be usefully applied on a wide range of fingerprint-type methodologies.
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Affiliation(s)
- Maurizio Cardelli
- Italian National Research Centers on Aging (I.N.R.C.A.), Ancona, Italy
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Liu Z, Venkatesh SS, Maley CC. Sequence space coverage, entropy of genomes and the potential to detect non-human DNA in human samples. BMC Genomics 2008; 9:509. [PMID: 18973670 PMCID: PMC2628393 DOI: 10.1186/1471-2164-9-509] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2008] [Accepted: 10/30/2008] [Indexed: 12/17/2022] Open
Abstract
Background Genomes store information for building and maintaining organisms. Complete sequencing of many genomes provides the opportunity to study and compare global information properties of those genomes. Results We have analyzed aspects of the information content of Homo sapiens, Mus musculus, Drosophila melanogaster, Caenorhabditis elegans, Arabidopsis thaliana, Saccharomyces cerevisiae, and Escherichia coli (K-12) genomes. Virtually all possible (> 98%) 12 bp oligomers appear in vertebrate genomes while < 2% of 19 bp oligomers are present. Other species showed different ranges of > 98% to < 2% of possible oligomers in D. melanogaster (12–17 bp), C. elegans (11–17 bp), A. thaliana (11–17 bp), S. cerevisiae (10–16 bp) and E. coli (9–15 bp). Frequencies of unique oligomers in the genomes follow similar patterns. We identified a set of 2.6 M 15-mers that are more than 1 nucleotide different from all 15-mers in the human genome and so could be used as probes to detect microbes in human samples. In a human sample, these probes would detect 100% of the 433 currently fully sequenced prokaryotes and 75% of the 3065 fully sequenced viruses. The human genome is significantly more compact in sequence space than a random genome. We identified the most frequent 5- to 20-mers in the human genome, which may prove useful as PCR primers. We also identified a bacterium, Anaeromyxobacter dehalogenans, which has an exceptionally low diversity of oligomers given the size of its genome and its GC content. The entropy of coding regions in the human genome is significantly higher than non-coding regions and chromosomes. However chromosomes 1, 2, 9, 12 and 14 have a relatively high proportion of coding DNA without high entropy, and chromosome 20 is the opposite with a low frequency of coding regions but relatively high entropy. Conclusion Measures of the frequency of oligomers are useful for designing PCR assays and for identifying chromosomes and organisms with hidden structure that had not been previously recognized. This information may be used to detect novel microbes in human tissues.
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Affiliation(s)
- Zhandong Liu
- Genomics and Computational Biology Graduate Group, School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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Montesanto A, Passarino G, Senatore A, Carotenuto L, De Benedictis G. Spatial Analysis and Surname Analysis: Complementary Tools for Shedding Light on Human Longevity Patterns. Ann Hum Genet 2007; 72:253-60. [DOI: 10.1111/j.1469-1809.2007.00405.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- A. Montesanto
- Department of Cell Biology, University of Calabria. 87036 Rende, Italy
| | - G. Passarino
- Department of Cell Biology, University of Calabria. 87036 Rende, Italy
| | - A. Senatore
- Department of Soil Conservation, University of Calabria. 87036 Rende, Italy
| | - L. Carotenuto
- Department of Electronics, Informatics and System Science, University of Calabria. 87036 Rende, Italy
| | - G. De Benedictis
- Department of Cell Biology, University of Calabria. 87036 Rende, Italy
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De Benedictis G, Franceschi C. The unusual genetics of human longevity. SCIENCE OF AGING KNOWLEDGE ENVIRONMENT : SAGE KE 2006; 2006:pe20. [PMID: 16807484 DOI: 10.1126/sageke.2006.10.pe20] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
In no species other than humans do cultural, social, and biological factors interact with each other in modulating complex phenotypes. Thus, the identification of genetic factors that affect human longevity is a true challenge. The model of centenarians provides us a unique opportunity to tackle this challenge. In this Perspective, we discuss some recent findings (the impact of geography and demography on the longevity phenotype, the relationship between longevity and homozygosity, the role of the nuclear-mitochondrial genome cross-talk) by which new ideas are suggested, such as the concept of a complex allele timing as a pivotal process in modulating the probability of achieving longevity.
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Caselli G, Pozzi L, Vaupel JW, Deiana L, Pes G, Carru C, Franceschi C, Baggio G. Family clustering in Sardinian longevity: a genealogical approach. Exp Gerontol 2006; 41:727-36. [PMID: 16793232 DOI: 10.1016/j.exger.2006.05.009] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2006] [Revised: 05/11/2006] [Accepted: 05/16/2006] [Indexed: 10/24/2022]
Abstract
This paper aims to discuss the validation and family determinants affecting the longevity of Sardinian centenarians, using a genealogical approach. This preliminary study presents the first results of a genealogical tree reconstruction of selected centenarians aged 105 and over, from certain areas. These are mostly situated in the province of Nuoro, an area with the highest rate of centenarians and where the female-to-male sex ratio tends to be male-biased. An accurate centenarian age validation was performed that required a meticulous examination of numerous civil status records and parish registers. An important finding was that longevity occurs among the ascendants of a particular branch of the family. The data used are still provisional but, should it apply to other validated cases, it would provide empirical evidence of a genetic component in longevity. A more thorough examination of the data available may yield deeper insights into the role played by endogamy and consanguinity.
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Cardelli M, Marchegiani F, Cavallone L, Olivieri F, Giovagnetti S, Mugianesi E, Moresi R, Lisa R, Franceschi C. A Polymorphism of the YTHDF2 Gene (1p35) Located in an Alu-Rich Genomic Domain Is Associated With Human Longevity. J Gerontol A Biol Sci Med Sci 2006; 61:547-56. [PMID: 16799135 DOI: 10.1093/gerona/61.6.547] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The uneven distribution of Alu repetitive elements in the human genome is related to specific functional properties of genomic regions. We report the identification of a locus associated with human longevity in one of the chromosomal regions with the highest density of Alu elements, in 1p35. The locus, corresponding to a (TG)n microsatellite in the YTHDF2 gene, was identified by characterizing an "anonymous" marker detectable through inter-Alu fingerprinting, which previously evidenced an increased homozygosity in centenarians. After genotyping 412 participants of different ages, including 137 centenarians, we confirmed the increased homozygosity in centenarians at this locus, and observed a concomitantly increased frequency of the most frequent allele and the corresponding homozygous genotype. Remarkably, the same genotype was associated with increased YTHDF2 messenger RNA levels in immortalized lymphocytes. Finally, YTHDF2 messenger RNA resulted to be mainly expressed in testis and placenta. The data suggest a possible role of this locus in human longevity.
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Affiliation(s)
- Maurizio Cardelli
- Department of Gerontological Research, Italian National Research Center on Aging (I.N.R.C.A), Via Birarelli 8, 60100 Ancona, Italy.
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Srivastava T, Seth A, Datta K, Chosdol K, Chattopadhyay P, Sinha S. Inter-alu PCR detects high frequency of genetic alterations in glioma cells exposed to sub-lethal cisplatin. Int J Cancer 2005; 117:683-9. [PMID: 15912534 DOI: 10.1002/ijc.21057] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Increased genomic instability contributes to higher frequency of secondary drug resistance and neoplastic progression in tumors as well as in cells exposed to sub-lethal concentrations of chemotherapeutic agents. We have used PCR based DNA fingerprinting techniques of randomly amplified polymorphic DNA (RAPD) and inter-alu PCR to study this phenomenon in the tumor genome. The choice of the primer, either random (for RAPD) or specific (inter-alu PCR) can determine the nature of alterations being assessed. We have compared the inter-alu PCR and RAPD profiles of U87MG glioblastoma cells exposed to sequentially increasing low doses of cisplatin for 24 passages to that of untreated controls. Inter-alu PCR, with 2 primers, demonstrated a number of alterations in the treated cells, in the form of loss / gain and changes in the intensity of bands. No changes were observed by RAPD analysis with 5 primers, however, indicating a preferential increase in the alu mediated recombination frequency in the treated cells (p = 1.866 x 10(-4)). The number of changes observed with respect to the corresponding leucocyte DNA in the inter-alu PCR profile of 26 primary tumors (Grade II = 13; Grade IV = 13), resected before chemotherapy, for the 2 inter-alu primers was very small. We present a novel application of the inter-alu PCR in detecting alterations in long term cultured cells at low dose exposure to a chemotherapeutic agent. Our results suggest that alu mediated recombination may be important in cells exposed to sub-lethal doses of cisplatin but not in the genesis of primary glioma.
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Affiliation(s)
- Tapasya Srivastava
- Department of Biochemistry, All India Institute of Medical Sciences, New Delhi
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Franceschi C, Olivieri F, Marchegiani F, Cardelli M, Cavallone L, Capri M, Salvioli S, Valensin S, De Benedictis G, Di Iorio A, Caruso C, Paolisso G, Monti D. Genes involved in immune response/inflammation, IGF1/insulin pathway and response to oxidative stress play a major role in the genetics of human longevity: the lesson of centenarians. Mech Ageing Dev 2005; 126:351-61. [PMID: 15621218 DOI: 10.1016/j.mad.2004.08.028] [Citation(s) in RCA: 145] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In this paper, we review data of recent literature on the distribution in centenarians of candidate germ-line polymorphisms that likely affect the individual chance to reach the extreme limit of human life. On the basis of previous observations on the immunology, endocrinology and cellular biology of centenarians we focused on genes that regulate immune responses and inflammation (IL-6, IL-1 cluster, IL-10), genes involved in the insulin/IGF-I signalling pathway and genes that counteract oxidative stress (PON1). On the whole, data indicate that polymorphisms of these genes likely contribute to human longevity, in accord with observations emerging from a variety of animal models, and suggest that a common core of master genes and metabolic pathways are responsible for aging and longevity across animal species. Moreover, in the concern of our plan to discover new genetic factors related to longevity, we explored the possibility to by-pass the need of an a-priori choice of candidate genes, extending the search to genes and genomic regions of still unknown function. Alu sequences may be considered as good markers of highly variable and potentially unstable loci in functionally important genomic regions. We extensively screened Alu-rich genomic sites and found a new genomic region associated with longevity.
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Barbieri M, Bonafè M, Rizzo MR, Ragno E, Olivieri F, Marchegiani F, Franceschi C, Paolisso G. Gender specific association of genetic variation in peroxisome proliferator-activated receptor (PPAR)γ-2 with longevity. Exp Gerontol 2004; 39:1095-100. [PMID: 15236769 DOI: 10.1016/j.exger.2004.03.034] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2003] [Revised: 03/19/2004] [Accepted: 03/23/2004] [Indexed: 11/30/2022]
Abstract
Long-lived subjects have been shown to have peculiar anthropometric features (i.e. lower body mass index (BMI)) and metabolic parameters (i.e. improved insulin sensitivity). Life style and a genetic background potentially protective against the age-related metabolic derangement might contribute to such a particular phenotype. Peroxisome proliferator-activated receptor (PPAR)gamma-2 is an important regulator of adipose tissue metabolism, insulin sensitivity and inflammatory response. Thus, the potential role of genetic variability at Pro/Ala loci of PPARG gene on longevity was studied in 222 long-lived subjects and 250 aged subjects. We found a different Pro/Ala genotype frequency distribution between long-lived and aged men subjects, long-lived men having an increased frequency of Pro/Ala genotype (20 vs 8.5%); no differences was found when allele and genotype distribution of Pro/Ala gene polymorphism were analyzed in the two age group of women. Interestingly, subjects with Pro/Ala polymorphism had significantly lower BMI than Ala/Ala and Pro/Pro polymorphism. In conclusion, our study demonstrated that paraoxonase Pro/Ala gene polyporphism is associated with human longevity. Such an effect is probably due to the effect of Pro/Ala polymorphism on body composition and appears to be gender specific.
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Affiliation(s)
- Michelangela Barbieri
- Department of Geriatric Medicine and Metabolic Diseases, VI Divisione di Medicina Interna, II University of Naples, Piazza Miraglia 2, I-80138, Italy
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Zhang J, Asin-Cayuela J, Fish J, Michikawa Y, Bonafe M, Olivieri F, Passarino G, De Benedictis G, Franceschi C, Attardi G. Strikingly higher frequency in centenarians and twins of mtDNA mutation causing remodeling of replication origin in leukocytes. Proc Natl Acad Sci U S A 2003; 100:1116-21. [PMID: 12538859 PMCID: PMC298736 DOI: 10.1073/pnas.242719399] [Citation(s) in RCA: 127] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/25/2002] [Indexed: 11/18/2022] Open
Abstract
The presence of a genetic component in longevity is well known. Here, the association of a mtDNA mutation with a prolonged life span in humans was investigated. Large-scale screening of the mtDNA main control region in leukocytes from subjects of an Italian population revealed a homoplasmic C150T transition near an origin of heavy mtDNA-strand synthesis in approximately 17% of 52 subjects 99-106 years old, but, in contrast, in only 3.4% of 117 younger individuals (P = 0.0035). Evidence was obtained for the contribution of somatic events, under probable nuclear genetic control, to the striking selective accumulation of the mutation in centenarians. In another study, among leukocyte mtDNA samples from 20 monozygotic and 18 dizygotic twins, 60-75 years old, 30% (P = 0.0007) and 22% (P = 0.011), respectively, of the individuals involved exhibited the homoplasmic C150T mutation. In a different system, i.e., in five human fibroblast longitudinal studies, convincing evidence for the aging-related somatic expansion of the C150T mutation, up to homoplasmy, was obtained. Most significantly, 5' end analysis of nascent heavy mtDNA strands consistently revealed a new replication origin at position 149, substituting for that at 151, only in C150T mutation-carrying samples of fibroblasts or immortalized lymphocytes. Considering the aging-related health risks that the centenarians have survived and the developmental risks of twin gestations, it is proposed that selection for a remodeled replication origin, inherited or somatically acquired, provides a survival advantage and underlies the observed high incidence of the C150T mutation in centenarians and twins.
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Affiliation(s)
- Jin Zhang
- Division of Biology, California Institute of Technology, Pasadena, CA 91125, USA
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