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D'Amelio P. Vitamin D Deficiency and Risk of Metabolic Syndrome in Aging Men. World J Mens Health 2021; 39:291-301. [PMID: 33663024 PMCID: PMC7994656 DOI: 10.5534/wjmh.200189] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 12/10/2020] [Accepted: 12/22/2020] [Indexed: 12/11/2022] Open
Abstract
The elderly population is rapidly increasing; hence, the disability due to age-related diseases has become an important socioeconomic burden. Amongst age-related diseases cardiovascular ones (CVD) have a huge impact on morbidity and mortality and are associated with metabolic syndrome (MetS). Several studies investigated the role of hypovitaminosis D in the pathogenesis of MetS and of CVD, this review unravels the relationship between aging/senescence, vitamin D, gender, and pathogenesis of MetS.
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Affiliation(s)
- Patrizia D'Amelio
- Department of Internal Medicine, Service of Geriatric Medicine and Geriatric Rehabilitation, University of Lausanne Hospital Centre, Lausanne, Switzerland.
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2
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Lulkiewicz M, Bajsert J, Kopczynski P, Barczak W, Rubis B. Telomere length: how the length makes a difference. Mol Biol Rep 2020; 47:7181-7188. [PMID: 32876842 PMCID: PMC7561533 DOI: 10.1007/s11033-020-05551-y] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 05/23/2020] [Indexed: 12/22/2022]
Abstract
Telomerase is perceived as an immortality enzyme that might provide longevity to cells and whole organisms. Importantly, it is generally inactive in most somatic cells of healthy, adult men. Consequently, its substrates, i.e. telomeres, get shorter in most human cells with time. Noteworthy, cell life limitation due to telomere attrition during cell divisions, may not be as bad as it looks since longer cell life means longer exposition to harmful factors. Consequently, telomere length (attrition rate) becomes a factor that is responsible for inducing the signaling that leads to the elimination of cells that lived long enough to acquire severe damage. It seems that telomere length that depends on many different factors (including telomerase activity but also genetic factors, a hormonal profile that reflects sex, etc.) might become a useful marker of aging and exposition to stress. Thus in the current paper, we review the factors that affect telomere length in human cells focusing on sex that all together with different environmental and hormonal regulations as well as parental aspect affect telomere attrition rate. We also raise some limitations in the assessment of telomere length that hinders a trustworthy meta-analysis that might lead to acknowledgment of the real value of this parameter.
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Affiliation(s)
- M Lulkiewicz
- Department of Clinical Chemistry and Molecular Diagnostics, Poznan University of Medical Sciences, 49 Przybyszewskiego St., 60-355, Poznan, Poland
| | - J Bajsert
- Department of Clinical Chemistry and Molecular Diagnostics, Poznan University of Medical Sciences, 49 Przybyszewskiego St., 60-355, Poznan, Poland
| | - P Kopczynski
- Centre for Orthodontic Mini-Implants at the Department and Clinic of Maxillofacial Orthopedics and Orthodontics, Poznan University of Medical Sciences, 60-812, Poznan, Poland
| | - W Barczak
- Department of Head and Neck Surgery, Poznan University of Medical Sciences, The Greater Poland Cancer Centre, 61-866, Poznan, Poland.,Radiobiology Laboratory, Department of Medical Physics, The Greater Poland Cancer Centre, 61-866, Poznan, Poland
| | - B Rubis
- Department of Clinical Chemistry and Molecular Diagnostics, Poznan University of Medical Sciences, 49 Przybyszewskiego St., 60-355, Poznan, Poland.
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3
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Derenzini E, Risso A, Ruella M, Spatola T, Milone G, Pioltelli P, Iori AP, Santarone S, Bosi A, Rambaldi A, Bacigalupo AP, Arcese W, Tarella C. Influence of Donor and Recipient Gender on Telomere Maintenance after Umbilical Cord Blood Cell Transplantation: A Study by the Gruppo Italiano Trapianto Di Midollo Osseo. Biol Blood Marrow Transplant 2019; 25:1387-1394. [PMID: 30935966 DOI: 10.1016/j.bbmt.2019.03.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2018] [Accepted: 03/24/2019] [Indexed: 12/13/2022]
Abstract
Physiologic loss of telomerase activity in adult life determines progressive telomere length (TL) shortening. Inflammation and oxidative damage are established causes of TL loss; moreover, males have shorter telomeres compared with females. Despite these notions, mechanisms regulating TL maintenance are poorly defined. Because umbilical cord blood (UCB) cells harbor very long telomeres, not yet exposed to environmental damages, UCB transplantation (UCBT) provides a unique experimental setting to study determinants of TL in humans. TL dynamics were analyzed on peripheral blood mononuclear cells (MNCs) from 36 patients (median age, 42 years) undergoing UCBT. TL was studied at a median of 20 months after UCBT. A significantly longer TL (mean, 8698 bp; range, 6521 to 11,960) was documented in UCBT recipients compared with age-matched healthy control subjects (mean, 7396 bp; range, 4375 to 11,108; P < .01). Among variables potentially influencing TL maintenance, including recipient features, graft type, transplant procedure, and engraftment kinetics, only donor-recipient gender combination was associated with TL, with the longest TL in women receiving male UCB (mean, 10,063 bp; range, 8381 to 11,960). To further investigate this trend, telomerase activation was assessed in vitro. Experiments showed that telomerase subunits were preferentially upregulated in male-derived bone marrow MNCs exposed ex vivo to estradiol as compared with female MNCs. This implies an increased sensitivity of male-derived MNCs to telomerase activation induced by estradiol. The results suggest that extrinsic and modifiable factors such as hormonal status and female milieu could be major determinants of TL in humans, providing the rationale for investigating hormonal-based approaches to counteract telomere erosion and aging-related diseases.
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Affiliation(s)
- Enrico Derenzini
- Oncohematology Division, IEO European Institute of Oncology, IRCCS, Milan, Italy
| | - Alessandra Risso
- Molecular Biotechnology Center Hematology & Cell Therapy Unit at Mauriziano H., Torino, Italy
| | - Marco Ruella
- Center for Cellular Immunotherapies & Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Tiziana Spatola
- Molecular Biotechnology Center Hematology & Cell Therapy Unit at Mauriziano H., Torino, Italy
| | - Giuseppe Milone
- Hematology and BMT Unit, Ospedale Ferrarotto, Catania, Italy
| | | | - Anna Paola Iori
- Division of Hematology, Department of Cellular Biotech & Hematol, 'Sapienza' University, Rome, Italy
| | - Stella Santarone
- Bone Marrow Transplant Center, Spirito Santo Hospital, Pescara, Italy
| | - Alberto Bosi
- Hematology Department, University of Florence and AOU Careggi, Florence, Italy
| | - Alessandro Rambaldi
- Department of Oncology and Hematology, ASST Papa Giovanni XXIII, Bergamo, Italy; University of Milan, Milan, Italy
| | | | - William Arcese
- Hematology Division-Stem Cell Transplant Unit, University of Rome Tor Vergata, Rome, Italy
| | - Corrado Tarella
- Oncohematology Division, IEO European Institute of Oncology, IRCCS, Milan, Italy; University of Milan, Milan, Italy.
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4
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Opstad TB, Kalstad AA, Pettersen AÅ, Arnesen H, Seljeflot I. Novel biomolecules of ageing, sex differences and potential underlying mechanisms of telomere shortening in coronary artery disease. Exp Gerontol 2019; 119:53-60. [PMID: 30684534 DOI: 10.1016/j.exger.2019.01.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 01/08/2019] [Accepted: 01/21/2019] [Indexed: 10/27/2022]
Abstract
Telomere length (TL), growth differentiate factor (GDF)11, insulin growth factor (IGF)1, sirtuin (SIRT)1 and inflammatory processes have been related to ageing and age-related diseases, like coronary artery disease (CAD). We aimed to investigate the associations between leukocyte TLs (LTLs), chronological age, sex and comorbidities in CAD patients. Any covariations between LTL, GDF11, IGF1, SIRT-1 and pro-inflammatory cytokines were further assessed. METHODS In 300 patients with stable CAD (age 36-81 years, 20% females), DNA and RNA were isolated from whole blood for PCR analysis and relative quantification of LTLs and gene-expression of GDF11, IGF1,SIRT1, IL-12, IL-18 and IFNƴ, respectively. Serum was prepared for the analyses of circulating IL-18, IL-12, IL-6 and TNFα. RESULTS Patients with previous myocardial infarction (MI) presented with 20% shorter LTLs vs. patients without (p = 0.019) indicating LTLs to be of importance for CAD severity. The observation however, was only observed in men (p = 0.009, n = 115), in which the upper LTL quartile associated with 64% lower frequency of previous MI compared to quartile 1-3 (p = 0.005, adjusted). LTLs were not differently distributed according to sex or comorbidities such as hypertension, diabetes type 2 and metabolic syndrome. LTLs and GDF11 were inversely correlated to age (r = -0.17; p = 0.007 and r = -0.16; p = 0.010, respectively), however, separated in gender, LTL only in women (r = -0.37) and GDF11 only in men (r = -0.19) (p = 0.006, both). GDF11 and SIRT1 were strongly inter-correlated (r = 0.56, p ≤ 0.001), suggesting common upstream regulators. LTLs were moderately correlated to GDF11 and SIRT1 in overweight women (BMI ≥ 25 kg/m2) (r = 0.41; p = 0.027 and 0.43; p = 0.020, respectively), which may reflect common life-style influences on LTLs and these markers. In all women, we observed further that the highest LTL quartile associated with higher GDF11 and SIRT expression and lower circulating levels of IL-12, IL-18 and TNFα, as compared to quartile 1, which may indicate lifestyle influences on female LTLs. In men, the highest LTL quartile associated with lower IFNƴ expression and lower circulating TNFα. Overall, the results indicate an association between chronic low-grade inflammation and LTLs. CONCLUSIONS Shorter LTLs in CAD patients with previously suffered MI may indicate telomere attrition as part of its pathophysiology in men. The inverse association between LTLs and age exclusively in women underpins the previously reported decline in attrition rate in men with increasing age. As elevated GDF11 and SIRT1 along with attenuated pro-inflammatory cytokines seem to positively affect LTL in women, we hypothesize a potential sex-dimorphism in LTL regulation, which may implicate sex- adjusted health-preventive therapies.
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Affiliation(s)
- Trine B Opstad
- Center for Clinical Heart Research, Department of Cardiology, Oslo University Hospital, Ullevål, Norway; Center for Heart Failure Research, Oslo University Hospital, Norway; Faculty of Medicine, University of Oslo, Norway.
| | - Are A Kalstad
- Center for Clinical Heart Research, Department of Cardiology, Oslo University Hospital, Ullevål, Norway; Center for Heart Failure Research, Oslo University Hospital, Norway; Faculty of Medicine, University of Oslo, Norway
| | - Alf Åge Pettersen
- Center for Clinical Heart Research, Department of Cardiology, Oslo University Hospital, Ullevål, Norway; Center for Heart Failure Research, Oslo University Hospital, Norway; Ringerike Hospital, Vestre Viken HF, Norway
| | - Harald Arnesen
- Center for Clinical Heart Research, Department of Cardiology, Oslo University Hospital, Ullevål, Norway; Center for Heart Failure Research, Oslo University Hospital, Norway; Faculty of Medicine, University of Oslo, Norway
| | - Ingebjørg Seljeflot
- Center for Clinical Heart Research, Department of Cardiology, Oslo University Hospital, Ullevål, Norway; Center for Heart Failure Research, Oslo University Hospital, Norway; Faculty of Medicine, University of Oslo, Norway
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5
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Unusual Twinning Resulting in Chimerism: A Systematic Review on Monochorionic Dizygotic Twins. Twin Res Hum Genet 2017; 20:161-168. [DOI: 10.1017/thg.2017.4] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Traditionally, it is understood that dizygotic (DZ) twins always have a dichorionic placenta. However, with 8% blood chimerism in DZ twins, placental sharing is probably more common than previously has been recognized. In this article, we will review all available cases of monochorionic dizygotic (MCDZ) twins. A total of 31 twins have been described in literature. A monochorionic diamniotic placenta is reported in all cases. Assisted reproductive technology is responsible for the origin of the pregnancy in 82.1% of the cases. In 15.4% of the sex-discordant twins, a genital anomaly was reported in one of the twins. Chimerism is demonstrable in 90.3% of the twins, leading to various diagnostic difficulties. As this review shows that most MCDZ twins are discovered by accident, it can be argued that it is far more common than has been assumed until now. However, the prevalence is still unclear. Awareness of MCDZ twinning is important, with subsequently correct medical strategies. Similarly, the resulting (blood) chimerism is essential to consider in diagnostic procedures, pre- and postnatally. More research on the effect of placental transfusion between sex-discordant twins is required.
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6
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Abstract
Longevity differs between sexes, with females being longer-lived in most mammals, including humans. One hallmark of aging is the functional decline of stem cells. Thus, a key question is whether the aging of stem cells differs between males and females and whether this has consequences for disease and lifespan.
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Affiliation(s)
- Ben Dulken
- Stanford University Medical Scientist Training Program, Stanford University, Stanford, CA 94305, USA; Stem Cell Biology and Regenerative Medicine Ph.D. Program, Stanford University, Stanford, CA 94305, USA; Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Anne Brunet
- Department of Genetics, Stanford University, Stanford, CA 94305, USA; The Glenn Laboratories for the Biology of Aging, Stanford University, Stanford, CA 94305, USA.
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7
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Barasc H, Ferchaud S, Mary N, Cucchi MA, Lucena AN, Letron IR, Calgaro A, Bonnet N, Dudez AM, Yerle M, Ducos A, Pinton A. Cytogenetic analysis of somatic and germinal cells from 38,XX/38,XY phenotypically normal boars. Theriogenology 2013; 81:368-72.e1. [PMID: 24200468 DOI: 10.1016/j.theriogenology.2013.10.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Revised: 10/04/2013] [Accepted: 10/06/2013] [Indexed: 01/05/2023]
Abstract
Many chromosomal abnormalities have been reported to date in pigs. Most of them have been balanced structural rearrangements, especially reciprocal translocations. A few cases of XY/XX chimerism have also been diagnosed within the national systematic chromosomal control program of young purebred boars carried out in France. Until now, this kind of chromosomal abnormality has been mainly reported in intersex individuals. We investigated 38,XY/38,XX boars presenting apparently normal phenotypes to evaluate the potential effects of this particular chromosomal constitution on their reproductive performance. To do this, we analyzed (1) the chromosomal constitution of cells from different organs in one boar; (2) the aneuploidy rates for chromosomes X, Y, and 13 in sperm nuclei sampled from seven XY/XX boars. 2n = 38,XX cells were identified in different nonhematopoietic tissues including testis (frequency, <8%). Similar aneuploidy rates were observed in the sperm nuclei of XY/XX and normal individuals (controls). Altogether, these results suggest that the presence of XX cells had no or only a very limited effect on the reproduction abilities of the analyzed boars.
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Affiliation(s)
- Harmonie Barasc
- INRA, UMR 444, Génétique Cellulaire, Toulouse, France; Université de Toulouse, INP, ENVT, UMR 444, Génétique Cellulaire, Toulouse, France
| | - Stéphane Ferchaud
- GenESI Génétique, Expérimentation et Système Innovants Poitou Charentes, Saint-Pierre-d'Amilly, France
| | - Nicolas Mary
- INRA, UMR 444, Génétique Cellulaire, Toulouse, France; Université de Toulouse, INP, ENVT, UMR 444, Génétique Cellulaire, Toulouse, France
| | - Marie Adélaïde Cucchi
- INRA, UMR 444, Génétique Cellulaire, Toulouse, France; Université de Toulouse, INP, ENVT, UMR 444, Génétique Cellulaire, Toulouse, France
| | - Amalia Naranjo Lucena
- INRA, UMR 444, Génétique Cellulaire, Toulouse, France; Université de Toulouse, INP, ENVT, UMR 444, Génétique Cellulaire, Toulouse, France
| | - Isabelle Raymond Letron
- Université de Toulouse, INP, ENVT, UMS 006, Département des Sciences Biologiques et Fonctionnelles, Laboratoire d'Histopathologie, Toulouse, France
| | - Anne Calgaro
- INRA, UMR 444, Génétique Cellulaire, Toulouse, France; Université de Toulouse, INP, ENVT, UMR 444, Génétique Cellulaire, Toulouse, France
| | - Nathalie Bonnet
- INRA, UMR 444, Génétique Cellulaire, Toulouse, France; Université de Toulouse, INP, ENVT, UMR 444, Génétique Cellulaire, Toulouse, France
| | - Anne Marie Dudez
- INRA, UMR 444, Génétique Cellulaire, Toulouse, France; Université de Toulouse, INP, ENVT, UMR 444, Génétique Cellulaire, Toulouse, France
| | - Martine Yerle
- INRA, UMR 444, Génétique Cellulaire, Toulouse, France; Université de Toulouse, INP, ENVT, UMR 444, Génétique Cellulaire, Toulouse, France
| | - Alain Ducos
- INRA, UMR 444, Génétique Cellulaire, Toulouse, France; Université de Toulouse, INP, ENVT, UMR 444, Génétique Cellulaire, Toulouse, France
| | - Alain Pinton
- INRA, UMR 444, Génétique Cellulaire, Toulouse, France; Université de Toulouse, INP, ENVT, UMR 444, Génétique Cellulaire, Toulouse, France.
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8
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Abstract
Males and females often age at different rates resulting in longevity 'gender gaps', where one sex outlives the other. Why the sexes have different lifespans is an age-old question, still fiercely debated today. One cellular process related to lifespan, which is known to differ according to sex, is the rate at which the protective telomere chromosome caps are lost. In humans, men have shorter lifespans and greater telomere shortening. This has led to speculation in the medical literature that sex-specific telomere shortening is one cause of sex-specific mortality. However, telomere shortening may be a cause for and/or a consequence of the processes that govern survival, and to infer general principles from single-taxon studies may be misleading. Here, we review recent work on telomeres in a variety of animal taxa, including those with reverse sexual lifespan dimorphism (i.e., where males live longer), to establish whether sex-specific survival is generally associated with sex differences in telomere dynamics. By doing this, we attempt to tease apart the potential underlying causes for sex differences in telomere lengths in humans and highlight targets for future research across all taxa.
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Affiliation(s)
- Emma L B Barrett
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norfolk, UK.
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9
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Hawcutt D, Hammond B, Sibbring J, Gokhale D, Ellis I, Bricker L, Subhedar N. Twin–twin confusion syndrome: Blood chimerism in opposite sex dizygotic twins. J OBSTET GYNAECOL 2011; 31:446-8. [DOI: 10.3109/01443615.2011.570813] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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10
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Eisenberg DTA. An evolutionary review of human telomere biology: the thrifty telomere hypothesis and notes on potential adaptive paternal effects. Am J Hum Biol 2011; 23:149-67. [PMID: 21319244 DOI: 10.1002/ajhb.21127] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2010] [Revised: 08/03/2010] [Accepted: 09/30/2010] [Indexed: 12/14/2022] Open
Abstract
Telomeres, repetitive DNA sequences found at the ends of linear chromosomes, play a role in regulating cellular proliferation, and shorten with increasing age in proliferating human tissues. The rate of age-related shortening of telomeres is highest early in life and decreases with age. Shortened telomeres are thought to limit the proliferation of cells and are associated with increased morbidity and mortality. Although natural selection is widely assumed to operate against long telomeres because they entail increased cancer risk, the evidence for this is mixed. Instead, here it is proposed that telomere length is primarily limited by energetic constraints. Cell proliferation is energetically expensive, so shorter telomeres should lead to a thrifty phenotype. Shorter telomeres are proposed to restrain adaptive immunity as an energy saving mechanism. Such a limited immune system, however, might also result in chronic infections, inflammatory stress, premature aging, and death--a more "disposable soma." With an increased reproductive lifespan, the fitness costs of premature aging are higher and longer telomeres will be favored by selection. Telomeres exhibit a paternal effect whereby the offspring of older fathers have longer telomeres due to increased telomere lengths of sperm with age. This paternal effect is proposed to be an adaptive signal of the expected age of male reproduction in the environment offspring are born into. The offspring of lineages of older fathers will tend to have longer, and thereby less thrifty, telomeres, better preparing them for an environment with higher expected ages at reproduction.
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Affiliation(s)
- Dan T A Eisenberg
- Department of Anthropology, Northwestern University, Evanston, IL 60208-1330, USA.
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11
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Zwijnenburg PJG, Meijers-Heijboer H, Boomsma DI. Identical but not the same: the value of discordant monozygotic twins in genetic research. Am J Med Genet B Neuropsychiatr Genet 2010; 153B:1134-49. [PMID: 20468073 DOI: 10.1002/ajmg.b.31091] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Monozygotic (MZ) twins show remarkable resemblance in many aspects of behavior, health, and disease. Until recently, MZ twins were usually called "genetically identical"; however, evidence for genetic and epigenetic differences within rare MZ twin pairs has accumulated. Here, we summarize the literature on MZ twins discordant for Mendelian inherited disorders and chromosomal abnormalities. A systematic literature search for English articles on discordant MZ twin pairs was performed in Web of Science and PubMed. A total number of 2,016 publications were retrieved and reviewed and 439 reports were retained. Discordant MZ twin pairs are informative in respect to variability of phenotypic expression, pathogenetic mechanisms, epigenetics, and post-zygotic mutagenesis and may serve as a model for research on genetic defects. The analysis of single discordant MZ twin pairs may represent an elegant approach to identify genes in inherited disorders.
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Affiliation(s)
- Petra J G Zwijnenburg
- Department of Clinical Genetics, VU University Medical Center, de Boelelaan 1117, Amsterdam, the Netherlands.
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12
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Sex-related differences in length and erosion dynamics of human telomeres favor females. Aging (Albany NY) 2009; 1:733-9. [PMID: 20195387 PMCID: PMC2830083 DOI: 10.18632/aging.100068] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2008] [Accepted: 07/12/2009] [Indexed: 02/07/2023]
Abstract
Telomeres are repetitive DNA sequences at chromosomal ends contributing to genomic
integrity. In somatic cells, telomeres are shortened during DNA
reduplication. Thus, telomere erosion has been regarded as a biological
clock. Applying the telomere/centromere (T/C)-FISH technique to human
peripheral blood lymphocytes, we showed that pangenomically, telomere
shortening is linear in centenarians and that this attrition is delayed in
females. Statistics reveal a greater skewness in telomere length
distribution in females. As the morphological correlate, we find abnormally
long telomeres distributed at random. This "erratic extensive elongation"
(EEE) of telomeres is a hitherto unrecognized phenomenon in non-neoplastic
cells, and females are more successful in this respect. As evidenced by
endoreduplication, EEE is transmitted to the cells' progeny. The mechanism
involved is likely to be the alternative pathway of telomere elongation
(ALT), counteracting erosion and already known to operate in neoplastic
cells.
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13
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Paul L, Cattaneo M, D'Angelo A, Sampietro F, Fermo I, Razzari C, Fontana G, Eugene N, Jacques PF, Selhub J. Telomere length in peripheral blood mononuclear cells is associated with folate status in men. J Nutr 2009; 139:1273-8. [PMID: 19458030 DOI: 10.3945/jn.109.104984] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Human chromosomes are capped by telomeres, which consist of tandem repeats of DNA and associated proteins. The length of the telomeres is reduced with increasing cell divisions except when the enzyme telomerase is active, as in stem cells and germ cells. Telomere dysfunction has been associated with development of age-related pathologies, including cancer, cardiovascular disease, Alzheimer's disease, and Parkinson's disease. DNA damage in the telomeric region causes attrition of telomeres. Because folate provides precursors for nucleotide synthesis and thus affects the integrity of DNA, including that of the telomeric region, folate status has the potential to influence telomere length. Telomere length is epigenetically regulated by DNA methylation, which in turn could be modulated by folate status. In this study, we determined whether folate status and the 677C > T polymorphism of the methylene tetrahydrofolate reductase (MTHFR) gene are associated with the telomere length of peripheral blood mononuclear cells in healthy men. The results of our study showed that plasma concentration of folate was associated with telomere length of peripheral blood mononuclear cells in a nonlinear manner. When plasma folate concentration was above the median, there was a positive relationship between folate and telomere length. In contrast, there was an inverse relationship between folate and telomere length when plasma folate concentration was below the median. The MTHFR 677C > T polymorphism was weakly associated (P = 0.065) with increased telomere length at below-median folate status. We propose that folate status influences telomere length by affecting DNA integrity and the epigenetic regulation of telomere length through DNA methylation.
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Affiliation(s)
- Ligi Paul
- Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111, USA.
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