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Childebayeva A, Harman T, Weinstein J, Day T, Brutsaert TD, Bigham AW. Genome-Wide DNA Methylation Changes Associated With High-Altitude Acclimatization During an Everest Base Camp Trek. Front Physiol 2021; 12:660906. [PMID: 34262470 PMCID: PMC8273439 DOI: 10.3389/fphys.2021.660906] [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: 01/29/2021] [Accepted: 05/04/2021] [Indexed: 12/30/2022] Open
Abstract
The individual physiological response to high-altitude hypoxia involves both genetic and non-genetic factors, including epigenetic modifications. Epigenetic changes in hypoxia factor pathway (HIF) genes are associated with high-altitude acclimatization. However, genome-wide epigenetic changes that are associated with short-term hypoxia exposure remain largely unknown. We collected a series of DNA samples from 15 participants of European ancestry trekking to Everest Base Camp to identify DNA methylation changes associated with incremental altitude ascent. We determined genome-wide DNA methylation levels using the Illumina MethylationEPIC chip comparing two altitudes: baseline 1,400 m (day 0) and elevation 4,240 m (day 7). The results of our epigenome-wide association study revealed 2,873 significant differentially methylated positions (DMPs) and 361 significant differentially methylated regions (DMRs), including significant positions and regions in hypoxia inducible factor (HIF) and the renin–angiotensin system (RAS) pathways. Our pathway enrichment analysis identified 95 significant pathways including regulation of glycolytic process (GO:0006110), regulation of hematopoietic stem cell differentiation (GO:1902036), and regulation of angiogenesis (GO:0045765). Lastly, we identified an association between the ACE gene insertion/deletion (I/D) polymorphism and oxygen saturation, as well as average ACE methylation. These findings shed light on the genes and pathways experiencing the most epigenetic change associated with short-term exposure to hypoxia.
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Affiliation(s)
- Ainash Childebayeva
- Department of Anthropology, University of Michigan, Ann Arbor, MI, United States.,Department of Environmental Sciences, School of Public Health, Ann Arbor, MI, United States.,Department of Archaeogenetics, Max Planck Institute for the Study of Human History, Jena, Germany
| | - Taylor Harman
- Department of Anthropology, Syracuse University, Syracuse, NY, United States
| | - Julien Weinstein
- Department of Anthropology, University of Michigan, Ann Arbor, MI, United States
| | - Trevor Day
- Department of Biology, Mount Royal University, Calgary, AB, Canada
| | - Tom D Brutsaert
- Department of Exercise Science, Syracuse University, Syracuse, NY, United States
| | - Abigail W Bigham
- Department of Anthropology, University of California, Los Angeles, Los Angeles, CA, United States
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2
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Angiotensin-converting enzyme (ACE) insertion/deletion gene polymorphism across ethnicity: a narrative review of performance gene. SPORT SCIENCES FOR HEALTH 2021. [DOI: 10.1007/s11332-020-00712-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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3
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Kuperus E, van der Meijden JC, in ’t Groen SLM, Kroos MA, Hoogeveen-Westerveld M, Rizopoulos D, Martinez MYN, Kruijshaar ME, van Doorn PA, van der Beek NAME, van der Ploeg AT, Pijnappel WWMP. The ACE I/D polymorphism does not explain heterogeneity of natural course and response to enzyme replacement therapy in Pompe disease. PLoS One 2018; 13:e0208854. [PMID: 30532252 PMCID: PMC6285976 DOI: 10.1371/journal.pone.0208854] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 11/23/2018] [Indexed: 12/16/2022] Open
Abstract
The majority of children and adults with Pompe disease in the population of European descent carry the leaky splicing GAA variant c.-32-13T>G (IVS1) in combination with a fully deleterious GAA variant on the second allele. The phenotypic spectrum of this patient group is exceptionally broad, with symptom onset ranging from early infancy to late adulthood. In addition, the response to enzyme replacement therapy (ERT) varies between patients. The insertion/deletion (I/D) polymorphism of the angiotensin I-converting enzyme (ACE) has been suggested to be a modifier of disease onset and/or response to ERT. Here, we have investigated the effect of the ACE I/D polymorphism in a relatively large cohort of 131 children and adults with Pompe disease, of whom 112 were followed during treatment with ERT for 5 years. We assessed the use of wheelchair and mechanical ventilation, muscle strength assessed via manual muscle testing and hand-held dynamometry (HHD), distance walked on the six-minute walk test (6MWT), forced vital capacity (FVC) in sitting and supine position and daily-life activities assessed by R-PAct. Cross sectional analysis at first visit showed no differences between the genotypes with respect to age at first symptoms, diagnosis, wheelchair use, or ventilator use. Also response to ERT over 5 years assessed by linear mixed model analyses showed no significant differences between ACE groups for any of the outcome measures. The patient cohort contained 24 families with 54 siblings. Differences in ACE genotype could neither explain inter nor intra familial differences. We conclude that the ACE I/D polymorphism does not explain the large variation in disease severity and response to ERT observed among Pompe patients with the same c.-32-13T>G GAA variant.
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Affiliation(s)
- Esther Kuperus
- Center for Lysosomal and Metabolic Diseases, Erasmus MC University Medical Center, Rotterdam, the Netherlands
- Department of Neurology, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Jan C. van der Meijden
- Center for Lysosomal and Metabolic Diseases, Erasmus MC University Medical Center, Rotterdam, the Netherlands
- Department of Pediatrics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Stijn L. M. in ’t Groen
- Center for Lysosomal and Metabolic Diseases, Erasmus MC University Medical Center, Rotterdam, the Netherlands
- Department of Pediatrics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Marian A. Kroos
- Center for Lysosomal and Metabolic Diseases, Erasmus MC University Medical Center, Rotterdam, the Netherlands
- Department of Pediatrics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Marianne Hoogeveen-Westerveld
- Center for Lysosomal and Metabolic Diseases, Erasmus MC University Medical Center, Rotterdam, the Netherlands
- Department of Pediatrics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Dimitris Rizopoulos
- Department of Biostatistics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Monica Yasmin Nino Martinez
- Center for Lysosomal and Metabolic Diseases, Erasmus MC University Medical Center, Rotterdam, the Netherlands
- Department of Pediatrics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Michelle E. Kruijshaar
- Center for Lysosomal and Metabolic Diseases, Erasmus MC University Medical Center, Rotterdam, the Netherlands
- Department of Pediatrics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Pieter A. van Doorn
- Center for Lysosomal and Metabolic Diseases, Erasmus MC University Medical Center, Rotterdam, the Netherlands
- Department of Neurology, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Nadine A. M. E. van der Beek
- Center for Lysosomal and Metabolic Diseases, Erasmus MC University Medical Center, Rotterdam, the Netherlands
- Department of Neurology, Erasmus MC University Medical Center, Rotterdam, the Netherlands
- * E-mail: (WP); (NvdB)
| | - Ans T. van der Ploeg
- Center for Lysosomal and Metabolic Diseases, Erasmus MC University Medical Center, Rotterdam, the Netherlands
- Department of Pediatrics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - W. W. M. Pim Pijnappel
- Center for Lysosomal and Metabolic Diseases, Erasmus MC University Medical Center, Rotterdam, the Netherlands
- Department of Pediatrics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
- * E-mail: (WP); (NvdB)
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4
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The influence of angiotensin-converting enzyme gene ID polymorphism on human physical fitness performance in European and other populations. SPORT SCIENCES FOR HEALTH 2017. [DOI: 10.1007/s11332-016-0340-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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5
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Shader RI. Forgotten Influences and Reflections on Exercise and on the End of the Year 2017. Clin Ther 2017; 39:2331-2336. [PMID: 29180060 DOI: 10.1016/j.clinthera.2017.11.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 11/10/2017] [Indexed: 10/18/2022]
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6
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Buroker NE, Ning XH, Zhou ZN, Li K, Cen WJ, Wu XF, Zhu WZ, Scott CR, Chen SH. SNPs, linkage disequilibrium, and chronic mountain sickness in Tibetan Chinese. HYPOXIA 2017; 5:67-74. [PMID: 28770234 PMCID: PMC5529112 DOI: 10.2147/hp.s117967] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Chronic mountain sickness (CMS) is estimated at 1.2% in Tibetans living at the Qinghai-Tibetan Plateau. Eighteen single-nucleotide polymorphisms (SNPs) from nine nuclear genes that have an association with CMS in Tibetans have been analyzed by using pairwise linkage disequilibrium (LD). The SNPs included are the angiotensin-converting enzyme (rs4340), the angiotensinogen (rs699), and the angiotensin II type 1 receptor (AGTR1) (rs5186) from the renin-angiotensin system. A low-density lipoprotein apolipoprotein B (rs693) SNP was also included. From the hypoxia-inducible factor oxygen signaling pathway, the endothetal Per-Arnt-Sim domain protein 1 (EPAS1) and the egl nine homolog 1 (ENGL1) (rs480902) SNPs were included in the study. SNPs from the vascular endothelial growth factor (VEGF) signaling pathway included are the v-akt murine thymoma viral oncogene homolog 3 (rs4590656 and rs2291409), the endothelial cell nitric oxide synthase 3 (rs1007311 and rs1799983), and the (VEGFA) (rs699947, rs34357231, rs79469752, rs13207351, rs28357093, rs1570360, rs2010963, and rs3025039). An increase in LD occurred in 40 pairwise comparisons, whereas a decrease in LD was found in 55 pairwise comparisons between the controls and CMS patients. These changes were found to occur within and between signaling pathways, which suggests that there is an interaction between SNP alleles from different areas of the genome that affect CMS.
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Affiliation(s)
| | - Xue-Han Ning
- Department of Pediatrics, University of Washington.,Division of Cardiology, Seattle Children's Hospital Research Foundation, Seattle, WA, USA
| | - Zhao-Nian Zhou
- Laboratory of Hypoxia Physiology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Kui Li
- Lhasa People Hospital, Lhasa, Tibet
| | | | - Xiu-Feng Wu
- Laboratory of Hypoxia Physiology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Wei-Zhong Zhu
- Center for Cardiovascular Biology and Regenerative Medicine, University of Washington, Seattle, WA, USA
| | | | - Shi-Han Chen
- Department of Pediatrics, University of Washington
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7
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MacInnis MJ, Koehle MS. Evidence for and Against Genetic Predispositions to Acute and Chronic Altitude Illnesses. High Alt Med Biol 2016; 17:281-293. [PMID: 27500591 DOI: 10.1089/ham.2016.0024] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
MacInnis, Martin J., and Michael S. Koehle. Evidence for and against genetic predispositions to acute and chronic altitude illnesses. High Alt Med Biol. 17:281-293, 2016.-Humans exhibit marked variation in their responses to hypoxia, with susceptibility to acute and chronic altitude illnesses being a prominent and medically important example. Many have hypothesized that genetic differences are the cause of these variable responses to hypoxia; however, until recently, these hypotheses were based primarily on small (and sometimes anecdotal) reports pertaining to apparent differences in altitude illness susceptibility between populations, the notion that a history of altitude illness is indicative of subsequent risk, the heritability of hypoxia-related traits, and candidate gene association studies. In the past 5 years, the use of genomic techniques has helped bolster the claim that susceptibility to some altitude illnesses is likely the result of genetic variation. For each of the major altitude illnesses, we summarize and evaluate the evidence stemming from three important characteristics of a genetic trait: (1) individual susceptibility and repeatability across assessments, (2) biogeographical differences and familial aggregation, and (3) association(s) with genetic variants. Evidence to support a genetic basis for susceptibilities to acute mountain sickness (AMS) and high-altitude cerebral edema (HACE) is limited, owing partially to the subjective and unclear phenotype of AMS and the rarity and severity of HACE. In contrast, recent genomic studies have identified genes that influence susceptibility to high-altitude pulmonary edema, chronic mountain sickness, and high-altitude pulmonary hypertension. The collection of more individual, familial, and biogeographical susceptibility data should improve our understanding of the extent to which genetic variation contributes to altitude illness susceptibility, and genomic and molecular investigations have the potential to elucidate the mechanisms that underpin altitude illness susceptibility.
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Affiliation(s)
| | - Michael S Koehle
- 2 School of Kinesiology, University of British Columbia , Vancouver, Canada .,3 Allan McGavin Sport Medicine Clinic, Department of Family Practice, University of British Columbia , Vancouver, Canada
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8
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Rees T, Hardy L, Güllich A, Abernethy B, Côté J, Woodman T, Montgomery H, Laing S, Warr C. The Great British Medalists Project: A Review of Current Knowledge on the Development of the World's Best Sporting Talent. Sports Med 2016; 46:1041-58. [PMID: 26842017 PMCID: PMC4963454 DOI: 10.1007/s40279-016-0476-2] [Citation(s) in RCA: 140] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The literature base regarding the development of sporting talent is extensive, and includes empirical articles, reviews, position papers, academic books, governing body documents, popular books, unpublished theses and anecdotal evidence, and contains numerous models of talent development. With such a varied body of work, the task for researchers, practitioners and policy makers of generating a clear understanding of what is known and what is thought to be true regarding the development of sporting talent is particularly challenging. Drawing on a wide array of expertise, we address this challenge by avoiding adherence to any specific model or area and by providing a reasoned review across three key overarching topics: (a) the performer; (b) the environment; and (c) practice and training. Within each topic sub-section, we review and calibrate evidence by performance level of the samples. We then conclude each sub-section with a brief summary, a rating of the quality of evidence, a recommendation for practice and suggestions for future research. These serve to highlight both our current level of understanding and our level of confidence in providing practice recommendations, but also point to a need for future studies that could offer evidence regarding the complex interactions that almost certainly exist across domains.
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Affiliation(s)
- Tim Rees
- Department of Sport and Physical Activity, Faculty of Management, Bournemouth University, Dorset House, Talbot Campus, Fern Barrow, Poole, BH12 5BB, UK.
| | - Lew Hardy
- Sport, Health and Exercise Sciences, Bangor University, George Building, Bangor, Gwynedd, LL57 2PZ, UK
| | - Arne Güllich
- Department of Sport Science, University of Kaiserslautern, Erwin Schrödinger Street, 67663, Kaiserslautern, Germany
| | - Bruce Abernethy
- School of Human Movement and Nutrition Sciences, Faculty of Health and Behavioral Sciences, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Jean Côté
- School of Kinesiology and Health Studies, SKHS Building 28 Division Street, Queen's University, Kingston, ON, K7L 3N, Canada
| | - Tim Woodman
- Sport, Health and Exercise Sciences, Bangor University, George Building, Bangor, Gwynedd, LL57 2PZ, UK
| | - Hugh Montgomery
- School of Life and Medical Sciences, University College London, Rockefeller Building, 20, University Street, London, WC1E 6DE, UK
| | - Stewart Laing
- UK Sport, 21 Bloomsbury Street, London, WC1B 3HF, UK
| | - Chelsea Warr
- UK Sport, 21 Bloomsbury Street, London, WC1B 3HF, UK
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9
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Dhamrait SS, Maubaret C, Pedersen-Bjergaard U, Brull DJ, Gohlke P, Payne JR, World M, Thorsteinsson B, Humphries SE, Montgomery HE. Mitochondrial uncoupling proteins regulate angiotensin-converting enzyme expression: crosstalk between cellular and endocrine metabolic regulators suggested by RNA interference and genetic studies. Bioessays 2016; 38 Suppl 1:S107-18. [DOI: 10.1002/bies.201670909] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 02/11/2015] [Indexed: 12/28/2022]
Affiliation(s)
- Sukhbir S. Dhamrait
- Centre for Cardiovascular Genetics, BHF Laboratories; University College London; London UK
- Department of Cardiology; Western Sussex Hospitals NHS Trust; West Sussex UK
| | - Cecilia Maubaret
- Centre INSERM U897-Epidemiologie-Biostatistique; Bordeaux France
| | - Ulrik Pedersen-Bjergaard
- Department of Cardiology, Nephrology and Endocrinology; Hillerød Hospital; Hillerød Denmark
- Faculty of Health Sciences; University of Copenhagen; Copenhagen Denmark
| | - David J. Brull
- Centre for Cardiovascular Genetics, BHF Laboratories; University College London; London UK
- Department of Cardiology; The Whittington Hospital NHS Trust; London UK
| | - Peter Gohlke
- Institute of Experimental and Clinical Pharmacology; University Hospital of Schleswig-Holstein; Kiel Germany
| | - John R. Payne
- Centre for Cardiovascular Genetics, BHF Laboratories; University College London; London UK
- Scottish National Advanced Heart Failure Service; Golden Jubilee National Hospital; Clydebank UK
| | - Michael World
- Royal Centre for Defence Medicine; Queen Elizabeth Hospital; Birmingham UK
| | - Birger Thorsteinsson
- Department of Cardiology, Nephrology and Endocrinology; Hillerød Hospital; Hillerød Denmark
- Faculty of Health Sciences; University of Copenhagen; Copenhagen Denmark
| | - Steve E. Humphries
- Centre for Cardiovascular Genetics, BHF Laboratories; University College London; London UK
| | - Hugh E. Montgomery
- UCL and National Centre for Sport, Exercise & Health; University College London; London UK
- UCL Institute for Human Health and Performance; University College London; London UK
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10
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Barker KR, Conroy AL, Hawkes M, Murphy H, Pandey P, Kain KC. Biomarkers of hypoxia, endothelial and circulatory dysfunction among climbers in Nepal with AMS and HAPE: a prospective case-control study. J Travel Med 2016; 23:taw005. [PMID: 26984355 PMCID: PMC5731443 DOI: 10.1093/jtm/taw005] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/11/2016] [Indexed: 12/12/2022]
Abstract
BACKGROUND The mechanisms underlying acute mountain sickness (AMS) and high-altitude pulmonary edema (HAPE) are not fully understood. We hypothesized that regulators of endothelial function, circulatory homeostasis, hypoxia and cell stress contribute to the pathobiology of AMS and HAPE. METHODS We conducted a prospective case-control study of climbers developing altitude illness who were evacuated to the CIWEC clinic in Kathmandu, compared to healthy acclimatized climbers. ELISA was used to measure plasma biomarkers of the above pathways. RESULTS Of the 175 participants, there were 71 cases of HAPE, 54 cases of AMS and 50 acclimatized controls (ACs). Markers of endothelial function were associated with HAPE: circulating levels of endothelin-1 (ET-1) were significantly elevated and levels of sKDR (soluble kinase domain receptor) were significantly decreased in cases of HAPE compared to AC or AMS. ET-1 levels were associated with disease severity as indicated by oxygen saturation. Angiopoietin-like 4 (Angptl4) and resistin, a marker of cell stress, were associated with AMS and HAPE irrespective of severity. Corin and angiotensin converting enzyme, regulators of volume homeostasis, were significantly decreased in HAPE compared to AC. CONCLUSION Our findings indicate that regulators of endothelial function, vascular tone and cell stress are altered in altitude illness and may mechanistically contribute to the pathobiology of HAPE.
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Affiliation(s)
- Kevin R Barker
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada, Sandra Rotman Centre for Global Health, University Health Network-Toronto General Hospital, Toronto, ON, Canada
| | - Andrea L Conroy
- Sandra Rotman Centre for Global Health, University Health Network-Toronto General Hospital, Toronto, ON, Canada
| | - Michael Hawkes
- Sandra Rotman Centre for Global Health, University Health Network-Toronto General Hospital, Toronto, ON, Canada, Division of Infectious Diseases, Department of Pediatrics, University of Alberta, Edmonton, AB, Canada and
| | - Holly Murphy
- CIWEC Hospital and Travel Medicine Center, Kathmandu, Nepal
| | - Prativa Pandey
- CIWEC Hospital and Travel Medicine Center, Kathmandu, Nepal
| | - Kevin C Kain
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada, Sandra Rotman Centre for Global Health, University Health Network-Toronto General Hospital, Toronto, ON, Canada, The Tropical Disease Unit, Department of Medicine, University of Toronto, Toronto, ON, Canada,
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11
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Masschelein E, Van Thienen R, Thomis M, Hespel P. High twin resemblance for sensitivity to hypoxia. Med Sci Sports Exerc 2016; 47:74-81. [PMID: 24870565 DOI: 10.1249/mss.0000000000000386] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE Physiological responses to hypoxia vary between individuals, and genetic factors are conceivably involved. Using a monozygotic twin design, we investigated the role of genetic factors in physiological responses to acute hypoxia. METHODS Thirteen pairs of monozygotic twin brothers participated in two experimental sessions in a normobaric hypoxic facility with a 2-wk interval. In one session, fraction of inspired O2 (FiO2) was gradually reduced to 10.7% (approximately 5300 m altitude) over 5 h. During the next 3 h at 10.7%, FiO2 subjects performed a 20-min submaximal exercise bout (EXSUB, 1.2 W·kg) and a maximal incremental exercise test (EXMAX). An identical control experiment was done in normoxia. Cardiorespiratory measurements were continuously performed, and 8-h urine output was collected. RESULTS Compared with normoxia, hypoxia decreased (P < 0.05) arterial O2 saturation (%SpO2) at rest (-22%) and during exercise (-28%). Furthermore, V˙O2max (-39%), HRmax (HR, -8%), maximal pulmonary ventilation (V˙Emax, -11%), and urinary norepinephrine excretion (-31%) were reduced (P < 0.05) whereas HR at rest (25%) and during EXSUB (16%) and V˙E at rest (38%) and during EXSUB (70%) were increased (P < 0.05). However, hypoxia-induced changes (Δ) were not randomly distributed between subjects. Between-pair variance was substantially larger than within-pair variance (P < 0.05) for Δ%SpO2 at rest (approximately threefold) and during exercise (approximately fourfold), ΔV˙O2max (approximately fourfold), ΔHR during exercise (approximately seven- to eightfold), hypoxic ventilatory response (approximately sixfold), and Δ urinary norepinephrine output (approximately threefold). Incidence of acute mountain sickness (AMS) also yielded significant twin similarity (P < 0.05). AMS subjects showed approximately 50% greater drop in urinary norepinephrine and lower hypoxic ventilator response than AMS individuals. CONCLUSIONS Our data suggest that genetic factors regulate cardiorespiratory responses, exercise tolerance, and pathogenesis of AMS symptoms in acute severe hypoxia. Hypoxia-induced sympathetic downregulation was associated with AMS.
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Affiliation(s)
- Evi Masschelein
- 1Exercise Physiology Research Group, Department of Kinesiology, KU Leuven, Leuven, BELGIUM; and 2Physical Activity, Sports and Health Research Group, Department of Kinesiology, KU Leuven, Leuven, BELGIUM
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12
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Hennis PJ, O'Doherty AF, Levett DZH, Grocott MPW, Montgomery HM. Genetic factors associated with exercise performance in atmospheric hypoxia. Sports Med 2016; 45:745-61. [PMID: 25682119 PMCID: PMC4544548 DOI: 10.1007/s40279-015-0309-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Background and Objective ‘Natural selection’ has been shown to have enriched the genomes of high-altitude native populations with genetic variants of advantage in this hostile hypoxic environment. In lowlanders who ascend to altitude, genetic factors may also contribute to the substantial interindividual variation in exercise performance noted at altitude. We performed a systematic literature review to identify genetic variants of possible influence on human hypoxic exercise performance, commenting on the strength of any identified associations. Criteria for considering studies for this review All studies of the association of genetic factors with human hypoxic exercise performance, whether at sea level using ‘nitrogen dilution of oxygen’ (normobaric hypoxia), or at altitude or in low-pressure chambers (field or chamber hypobaric hypoxia, respectively) were sought for review. Search strategy for identification of studies Two electronic databases were searched (Ovid MEDLINE, Embase) up to 31 January 2014. We also searched the reference lists of relevant articles for eligible studies. All studies published in English were included, as were studies in any language for which the abstract was available in English. Data collection and analysis Studies were selected and data extracted independently by two reviewers. Differences regarding study inclusion were resolved through discussion. The quality of each study was assessed using a scoring system based on published guidelines for conducting and reporting genetic association studies. Results A total of 11 studies met all inclusion criteria and were included in the review. Subject numbers ranged from 20 to 1,931 and consisted of healthy individuals in all cases. The maximum altitude of exposure ranged from 2,690 to 8,848 m. The exercise performance phenotypes assessed were mountaineering performance (n = 5), running performance (n = 2), and maximum oxygen consumption (\documentclass[12pt]{minimal}
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\begin{document}$$ \dot{V} $$\end{document}V˙O2max) (n = 4). In total, 13 genetic polymorphisms were studied, four of which were associated with hypoxic exercise performance. The adenosine monophosphate deaminase (AMPD1) C34T (rs17602729), beta2-adrenergic receptor (ADRB2) Gly16Arg single nucleotide polymorphism (SNP) (rs1042713), and androgen receptor CAG repeat polymorphisms were associated with altitude performance in one study, and the angiotensin I-converting enzyme (ACE) insertion/deletion (I/D) (rs4646994) polymorphism was associated with performance in three studies. The median score achieved in the study quality analysis was 6 out of 10 for case–control studies, 8 out of 10 for cohort studies with a discrete outcome, 6 out of 9 for cohort studies with a continuous outcome, and 4.5 out of 8 for genetic admixture studies. Conclusion The small number of articles identified in the current review and the limited number of polymorphisms studied in total highlights that the influence of genetic factors on exercise performance in hypoxia has not been studied in depth, which precludes firm conclusions being drawn. Support for the association between the ACE-I allele and improved high-altitude performance was the strongest, with three studies identifying a relationship. Analysis of study quality highlights the need for future studies in this field to improve the conduct and reporting of genetic association studies. Electronic supplementary material The online version of this article (doi:10.1007/s40279-015-0309-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Philip J Hennis
- UCLH NIHR Biomedical Research Centre, Institute of Sport and Exercise Health, University College London Centre for Altitude Space and Extreme Environment Medicine, 170 Tottenham Court Road, London, W1T 7HA, UK,
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Dhamrait SS, Maubaret C, Pedersen-Bjergaard U, Brull DJ, Gohlke P, Payne JR, World M, Thorsteinsson B, Humphries SE, Montgomery HE. Mitochondrial uncoupling proteins regulate angiotensin-converting enzyme expression: crosstalk between cellular and endocrine metabolic regulators suggested by RNA interference and genetic studies. ACTA ACUST UNITED AC 2015; 1:70-81. [PMID: 27347560 PMCID: PMC4915277 DOI: 10.1002/icl3.1019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 02/11/2015] [Indexed: 12/18/2022]
Abstract
Uncoupling proteins (UCPs) regulate mitochondrial function, and thus cellular metabolism. Angiotensin‐converting enzyme (ACE) is the central component of endocrine and local tissue renin–angiotensin systems (RAS), which also regulate diverse aspects of whole‐body metabolism and mitochondrial function (partly through altering mitochondrial UCP expression). We show that ACE expression also appears to be regulated by mitochondrial UCPs. In genetic analysis of two unrelated populations (healthy young UK men and Scandinavian diabetic patients) serum ACE (sACE) activity was significantly higher amongst UCP3‐55C (rather than T) and UCP2 I (rather than D) allele carriers. RNA interference against UCP2 in human umbilical vein endothelial cells reduced UCP2 mRNA sixfold (P < 0·01) whilst increasing ACE expression within a physiological range (<1·8‐fold at 48 h; P < 0·01). Our findings suggest novel hypotheses. Firstly, cellular feedback regulation may occur between UCPs and ACE. Secondly, cellular UCP regulation of sACE suggests a novel means of crosstalk between (and mutual regulation of) cellular and endocrine metabolism. This might partly explain the reduced risk of developing diabetes and metabolic syndrome with RAS antagonists and offer insight into the origins of cardiovascular disease in which UCPs and ACE both play a role.
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Affiliation(s)
- Sukhbir S Dhamrait
- Centre for Cardiovascular Genetics, BHF Laboratories University College London London UK; Department of Cardiology Western Sussex Hospitals NHS Trust West Sussex UK
| | | | - Ulrik Pedersen-Bjergaard
- Department of Cardiology, Nephrology and Endocrinology Hillerød Hospital Hillerød Denmark; Faculty of Health Sciences University of Copenhagen Copenhagen Denmark
| | - David J Brull
- Centre for Cardiovascular Genetics, BHF Laboratories University College London London UK; Department of Cardiology The Whittington Hospital NHS Trust London UK
| | - Peter Gohlke
- Institute of Experimental and Clinical Pharmacology University Hospital of Schleswig-Holstein Kiel Germany
| | - John R Payne
- Centre for Cardiovascular Genetics, BHF Laboratories University College London London UK; Scottish National Advanced Heart Failure Service Golden Jubilee National Hospital Clydebank UK
| | - Michael World
- Royal Centre for Defence Medicine Queen Elizabeth Hospital Birmingham UK
| | - Birger Thorsteinsson
- Department of Cardiology, Nephrology and Endocrinology Hillerød Hospital Hillerød Denmark; Faculty of Health Sciences University of Copenhagen Copenhagen Denmark
| | - Steve E Humphries
- Centre for Cardiovascular Genetics, BHF Laboratories University College London London UK
| | - Hugh E Montgomery
- UCL and National Centre for Sport, Exercise & Health University College London London UK; UCL Institute for Human Health and Performance University College London London UK
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Nicklas BJ. Heterogeneity of Physical Function Responses to Exercise in Older Adults: Possible Contribution of Variation in the Angiotensin-1 Converting Enzyme (ACE) Gene? PERSPECTIVES ON PSYCHOLOGICAL SCIENCE 2015; 5:575-84. [PMID: 26162198 DOI: 10.1177/1745691610383512] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Behavioral exercise interventions, aimed at improving either aerobic endurance or muscular strength, are currently the only therapy found, on average, to consistently retard loss of physical function in aging adults. However, not all individuals experience the same magnitude of benefit from a given exercise treatment, and certain persons may respond more favorably to a particular mode of exercise than another. Research now shows that genetic predisposition is one of the factors accounting for interindividual differences in responses to exercise as well as differences in the propensity to engage in exercise. This article discusses how a common variant in a single gene (the angiotensin-1 converting enzyme gene) could emerge as a prospective tool to identify older individuals more likely to benefit from and adhere to a specific type of exercise activity over another type.
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Affiliation(s)
- Barbara J Nicklas
- Department of Internal Medicine, Wake Forest University Health Sciences, Winston-Salem, NC
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Masschelein E, Puype J, Broos S, Van Thienen R, Deldicque L, Lambrechts D, Hespel P, Thomis M. A genetic predisposition score associates with reduced aerobic capacity in response to acute normobaric hypoxia in lowlanders. High Alt Med Biol 2015; 16:34-42. [PMID: 25761120 DOI: 10.1089/ham.2014.1083] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Given the high inter-individual variability in the sensitivity to high altitude, we hypothesize the presence of underlying genetic factors. The aim of this study was to construct a genetic predisposition score based on previously identified high-altitude gene variants to explain the inter-individual variation in the reduced maximal O2 uptake (ΔVo2max) in response to acute hypoxia. Ninety-six healthy young male Belgian lowlanders were included. In both normobaric normoxia (Fio2=20.9%) and acute normobaric hypoxia (Fio2=10.7%-12.5%) Vo2max was measured. Forty-one SNPs in 21 genes were genotyped. A stepwise regression analysis was applied to detect a subset of SNPs to be associated with ΔVo2max. This subset of SNPs was included in the genetic predisposition score. A general linear model and regression analysis with age, weight, height, hypoxic protocol group, and Vo2max in normoxia as covariates were used to test the explained variance of the genetic predisposition score. A ROC analysis was performed to discriminate between the low- and high ΔVo2max subgroups. A stepwise regression analysis revealed a subset of SNPs [rs833070 (VEGFA), rs4253778 (PPARA), rs6735530 (EPAS1), rs4341 (ACE), rs1042713 (ADRB2), and rs1042714 (ADRB2)] to be associated with ΔVo2max. The genetic predisposition score was found to be an independent predictive variable with a partial explained variance of 23% (p<0.0001). A ROC analysis showed significant discriminating accuracy (AUC=0.78, 95% confidence interval=0.64-0.91) between the low- and high ΔVo2max subgroups. This six-SNP based genetic predisposition score showed a significantly predictive value for ΔVo2max.
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Affiliation(s)
- Evi Masschelein
- 1 Exercise Physiology Research Group , KU Leuven, Leuven, Belgium
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16
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Bhagi S, Srivastava S, Tomar A, Bala Singh S, Sarkar S. Positive Association of D Allele of ACE Gene With High Altitude Pulmonary Edema in Indian Population. Wilderness Environ Med 2015; 26:124-32. [PMID: 25683681 DOI: 10.1016/j.wem.2014.09.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 09/01/2014] [Accepted: 09/06/2014] [Indexed: 11/25/2022]
Abstract
OBJECTIVE High altitude pulmonary edema (HAPE) is a potentially fatal high altitude illness occurring as a result of hypobaric hypoxia with an unknown underlying genetic mechanism. Recent studies have shown a possible association between HAPE and polymorphisms in genes of the renin-angiotensin-aldosterone system (RAAS), which play a key role in sensitivity of an individual toward HAPE. METHODS For the present investigation, study groups consisted of HAPE patients (HAPE) and acclimatized control subjects (rCON). Four single-nucleotide polymorphisms (SNPs) were genotyped using restriction fragment length polymorphism (RFLP) analysis in genes of the RAAS pathway, specifically, renin (REN) C(-4063)T (rs41317140) and RENi8-83 (rs2368564), angiotensin (AGT) M(235)T (rs699), and angiotensin-converting enzyme (ACE) insertion/deletion (I/D) (rs1799752). RESULTS Only the I/D polymorphism of the ACE gene showed a significant difference between the HAPE and rCON groups. The frequency of the D allele was found to be significantly higher in the HAPE group. Arterial oxygen saturation levels were significantly lower in the HAPE group compared with the rCON group and also decreased in the I/D and D/D genotypes compared with the I/I genotype in these groups. The other polymorphisms occurring in the REN and AGT genes were not significantly different between the 2 groups. CONCLUSIONS These findings demonstrate a possible association of the I/D polymorphism of the ACE gene with the development of HAPE, with D/D being the at-risk genotype.
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Affiliation(s)
- Shuchi Bhagi
- Defence Institute of Physiology and Allied Sciences, Defence Research and Development Organization, Delhi, India (Ms Bhagi, Drs Srivastava, Singh, and Sarkar)
| | - Swati Srivastava
- Defence Institute of Physiology and Allied Sciences, Defence Research and Development Organization, Delhi, India (Ms Bhagi, Drs Srivastava, Singh, and Sarkar).
| | - Arvind Tomar
- Defence Research and Development Establishment, Defence Research and Development Organization, Gwalior, India (Mr Tomar)
| | - Shashi Bala Singh
- Defence Institute of Physiology and Allied Sciences, Defence Research and Development Organization, Delhi, India (Ms Bhagi, Drs Srivastava, Singh, and Sarkar)
| | - Soma Sarkar
- Defence Institute of Physiology and Allied Sciences, Defence Research and Development Organization, Delhi, India (Ms Bhagi, Drs Srivastava, Singh, and Sarkar)
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Verlengia R, Rebelo AC, Crisp AH, Kunz VC, dos Santos Carneiro Cordeiro MA, Hirata MH, Crespo Hirata RD, Silva E. Lack of Association Between ACE Indel Polymorphism and Cardiorespiratory Fitness in Physically Active and Sedentary Young Women. Asian J Sports Med 2014; 5:e22768. [PMID: 25520764 PMCID: PMC4267487 DOI: 10.5812/asjsm.22768] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Accepted: 04/04/2014] [Indexed: 11/22/2022] Open
Abstract
Background: Polymorphisms at the angiotensin-converting enzyme gene (ACE), such as the indel [rs1799752] variant in intron 16, have been shown to be associated with aerobic performance of athletes and non-athletes. However, the relationship between ACE indel polymorphism and cardiorespiratory fitness has not been always demonstrated. Objectives: The relationship between ACE indel polymorphism and cardiorespiratory fitness was investigated in a sample of young Caucasian Brazilian women. Patients and Methods: This study investigated 117 healthy women (aged 18 to 30 years) who were grouped as physically active (n = 59) or sedentary (n = 58). All subjects performed an incremental exercise test (ramp protocol) on a cycle-ergometer with 20-25 W/min increments. Blood samples were obtained for DNA extraction and to analyze metabolic and hormonal profiles. ACE indel polymorphism was determined by polymerase chain reaction (PCR) and fragment size analysis. Results: The physically active group had higher values of peak oxygen uptake (VO2 peak), carbon dioxide output (VCO2), ventilation (VE) and power output than the sedentary group (P < 0.05) at the peak of the exercise test. However, heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP) did not differ between groups. There was no relationship between ACE indel polymorphism and cardiorespiratory variables during the test in both the physically active and sedentary groups, even when the dominant (DD vs. D1 + 2) and recessive (2 vs. DI + DD) models of inheritance were tested. Conclusions: These results do not support the concept that the genetic variation at the ACE locus contributes to the cardiorespiratory responses at the peak of exercise test in physically active or sedentary healthy women. This indicates that other factors might mediate these responses, including the physical training level of the women.
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Affiliation(s)
- Rozangela Verlengia
- College of Health Sciences, Methodist University of Piracicaba, Piracicaba, Brazil
- Corresponding author: Rozangela Verlengia, College of Health Sciences, Methodist University of Piracicaba, Piracicaba, Sao Paulo, Brazil. Tel: +55-151931241558, Fax: +55-151931241659, E-mail:, E-mail:
| | - Ana C. Rebelo
- Department of Morphology, Federal University of Goias, Goiania, Brazil
| | - Alex H. Crisp
- College of Health Sciences, Methodist University of Piracicaba, Piracicaba, Brazil
| | - Vandeni C. Kunz
- Adventist University of Sao Paulo, Engenheiro Coellho, Sao Paulo, Brazil
| | | | - Mario H. Hirata
- School of Pharmaceutical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | | | - Ester Silva
- Department of Physiotherapy, Federal University of Sao Carlos, Sao Carlos, Brazil
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18
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Djarova T, Bardarev D, Boyanov D, Kaneva R, Atanasov P. Performance enhancing genetic variants, oxygen uptake, heart rate, blood pressure and body mass index of elite high altitude mountaineers. ACTA ACUST UNITED AC 2013; 100:289-301. [PMID: 24058088 DOI: 10.1556/aphysiol.100.2013.3.5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
AIM To analyse and compare the ACE (angiotensin-converting enzyme), ACTN3 (actinin-3) and AMPD1 (adenosine monophosphate deaminase 1) genetic variants, oxygen uptake (VO2max), heart rate (HR), blood pressure (BP) and body mass index (BMI) of elite high altitude mountaineers and average athletes. METHODS Elite Bulgarian alpinists (n = 5) and control group of athletes (n = 72) were recruited. VO2max was measured using a treadmill graded protocol. HR, BP and BMI were recorded. Genotyping was done by polymerase chain reaction (PCR) amplification followed by agarose gel electrophoresis. Chi2-test and Fisher's exact test were used for statistical analysis. RESULTS Alpinists showed significantly higher frequencies of 60% ACE I allele (p = 0.002), 50% ACTN3 X allele (p = 0.032) and 30% AMPD1 T allele (p = 0.003) compared to controls - 39%, 36%, 13%, respectively. ACE ID genotype prevalence and null DD genotype were observed in mountaineers. Higher absolute VO2max, but no differences in VO2max ml kg-1 min-1, HR, oxygen pulse, blood pressure and BMI were found. CONCLUSIONS The ID genotype and higher frequencies of ACE I allele could contribute to successful high altitude ascents in mountaineers. The genetic make-up of the two mountaineers who made the summit of Mt Everest was distinctive, revealing ACE ID genotype, mutant ACTN3 XX and AMPD1 TT genotypes.
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Affiliation(s)
- T Djarova
- University of Zululand, South Africa Department of Biochemistry and Microbiology Private Bag X1001 KwaDlangezwa 3886 South Africa
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Puthucheary Z, Skipworth JRA, Rawal J, Loosemore M, Van Someren K, Montgomery HE. The ACE gene and human performance: 12 years on. Sports Med 2011; 41:433-48. [PMID: 21615186 DOI: 10.2165/11588720-000000000-00000] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Some 12 years ago, a polymorphism of the angiotensin I-converting enzyme (ACE) gene became the first genetic element shown to impact substantially on human physical performance. The renin-angiotensin system (RAS) exists not just as an endocrine regulator, but also within local tissue and cells, where it serves a variety of functions. Functional genetic polymorphic variants have been identified for most components of RAS, of which the best known and studied is a polymorphism of the ACE gene. The ACE insertion/deletion (I/D) polymorphism has been associated with improvements in performance and exercise duration in a variety of populations. The I allele has been consistently demonstrated to be associated with endurance-orientated events, notably, in triathlons. Meanwhile, the D allele is associated with strength- and power-orientated performance, and has been found in significant excess among elite swimmers. Exceptions to these associations do exist, and are discussed. In theory, associations with ACE genotype may be due to functional variants in nearby loci, and/or related genetic polymorphism such as the angiotensin receptor, growth hormone and bradykinin genes. Studies of growth hormone gene variants have not shown significant associations with performance in studies involving both triathletes and military recruits. The angiotensin type-1 receptor has two functional polymorphisms that have not been shown to be associated with performance, although studies of hypoxic ascent have yielded conflicting results. ACE genotype influences bradykinin levels, and a common gene variant in the bradykinin 2 receptor exists. The high kinin activity haplotye has been associated with increased endurance performance at an Olympic level, and similar results of metabolic efficiency have been demonstrated in triathletes. Whilst the ACE genotype is associated with overall performance ability, at a single organ level, the ACE genotype and related polymorphism have significant associations. In cardiac muscle, ACE genotype has associations with left ventricular mass changes in response to stimulus, in both the health and diseased states. The D allele is associated with an exaggerated response to training, and the I allele with the lowest cardiac growth response. In light of the I-allele association with endurance performance, it seems likely that other regulatory mechanisms exist. Similarly in skeletal muscle, the D allele is associated with greater strength gains in response to training, in both healthy individuals and chronic disease states. As in overall performance, those genetic polymorphisms related to the ACE genotype, such as the bradykinin 2 gene, also influence skeletal muscle strength. Finally, the ACE genotype may influence metabolic efficiency, and elite mountaineers have demonstrated an excess of I alleles and I/I genotype frequency in comparison to controls. Interestingly, this was not seen in amateur climbers. Corroboratory evidence exists among high-altitude settlements in both South America and India, where the I allele exists in greater frequency in those who migrated from the lowlands. Unfortunately, if the ACE genotype does influence metabolic efficiency, associations with peak maximal oxygen consumption have yet to be rigorously demonstrated. The ACE genotype is an important but single factor in the determinant of sporting phenotype. Much of the mechanisms underlying this remain unexplored despite 12 years of research.
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Affiliation(s)
- Zudin Puthucheary
- University College London Institute for Human Health and Performance, London, UK.
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20
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The genetics of altitude tolerance: the evidence for inherited susceptibility to acute mountain sickness. J Occup Environ Med 2011; 53:159-68. [PMID: 21270658 DOI: 10.1097/jom.0b013e318206b112] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVE Acute mountain sickness (AMS) has become a significant environmental health issue as improvements in transportation, "environmental tourism," and resource development lure more people to the highlands. Whether there is a genetic contribution to AMS susceptibility is a central question in high-altitude medicine. This article provides a systematic review of the evidence supporting such an innate predisposition. METHODS Scientific literature databases were screened using the terms "acute mountain sickness/AMS" and "altitude illness" combined with the terms "DNA," "gene," "genetic," or "polymorphism." RESULTS Sixteen genes from a variety of pathways have been tested for association with AMS and variants in eight showed positive associations suggesting that AMS is an environmentally mediated polygenic disorder. CONCLUSIONS The data suggest that genotype contributes to capacity to rapidly and efficiently acclimatize to altitude; nevertheless, the mechanisms by which this occurs have yet to be elucidated.
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21
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MacInnis MJ, Koehle MS, Rupert JL. Evidence for a genetic basis for altitude illness: 2010 update. High Alt Med Biol 2011; 11:349-68. [PMID: 21190504 DOI: 10.1089/ham.2010.1030] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Altitude illness refers to a group of environmentally mediated pathophysiologies. Many people will suffer acute mountain sickness shortly after rapidly ascending to a moderately hypoxic environment, and an unfortunate few will develop potentially fatal conditions such as high altitude pulmonary edema or high altitude cerebral edema. Some individuals seem to be predisposed to developing altitude illness, suggesting an innate contribution to susceptibility. The implication that there are altitude-sensitive and altitude-tolerant individuals has stimulated much research into the contribution of a genetic background to the efficacy of altitude acclimatization. Although the effect of altitude attained and rate of ascent on the etiology of altitude illness is well known, there are only tantalizing, but rapidly accumulating, clues to the genes that may be involved. In 2006, we reviewed what was then known about the genetics of altitude illness. This article updates that review and attempts to tabulate all the available genetic data pertaining to these conditions. To date, 58 genes have been investigated for a role in altitude illness. Of these, 17 have shown some association with the susceptibility to, or the severity of, these conditions, although in many cases the effect size is small or variable. Caution is recommended when evaluating the genes for which no association was detected, because a number of the investigations reviewed in this article were insufficiently powered to detect small effects. No study has demonstrated a clear-cut altitude illness gene, but the accumulating data are consistent with a polygenic condition with a strong environmental component. The genes that have shown an association affect a variety of biological pathways, suggesting that either multiple systems are involved in altitude pathophysiology or that gene-gene interactions play a role. Although numerous studies have been performed to investigate specific genes, few have looked for evidence of heritability or familial transmission, or for epidemiological patterns that would be consistent with genetically influenced conditions. Future trends, such as genome-wide association studies and epigenetic analysis, should lead to enhanced understanding of the complex interactions within the genome and between the genome and hypoxic environments that contribute to an individual's capacity to acclimatize rapidly and effectively to altitude.
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Affiliation(s)
- Martin J MacInnis
- School of Human Kinetics, University of British Columbia, 6081 University Boulevard, Vancouver, BC, Canada
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22
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Buroker NE, Ning XH, Zhou ZN, Li K, Cen WJ, Wu XF, Ge M, Fan LP, Zhu WZ, Portman MA, Chen SH. Genetic associations with mountain sickness in Han and Tibetan residents at the Qinghai-Tibetan Plateau. Clin Chim Acta 2010; 411:1466-73. [PMID: 20570668 DOI: 10.1016/j.cca.2010.05.043] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2010] [Revised: 05/28/2010] [Accepted: 05/29/2010] [Indexed: 10/19/2022]
Abstract
BACKGROUND Acute (AMS) and chronic (CMS) mountain sicknesses are illnesses that occur among humans visiting or inhabiting high-altitude environments, respectively. Some individuals are genetically less fit than others when stressed by an extreme high-altitude environment. Seven blood physiological parameters and five genetic polymorphisms were studied in Han patients with AMS and Tibetan patients with CMS. METHODS We compared 98 AMS patients with 60 Han controls as well as 50 CMS patients with 36 Tibetan controls. The genetic loci studied are ACE I/D (rs4340), AGT M235T (rs699), AGTR1 A1166C (rs5186), GNB3 A(-350)G (rs2071057) and APOB A/G (rs693). RESULTS All physiological parameters (RBC, HCT, Hb, SaO(2), HR, and BPs/d) studied significantly changed in the CMS patients while SaO(2) and HR changed in the AMS Han patients compared to their controls. The ACE D and AGT 235M alleles were found to be significantly associated with AMS and CMS, respectively, while a significantly high incidence of the G-protein (GNB3) (-350)A allele was found in the AMS patients. ACE (I/D) was significantly associated with HR in CMS patients while the AGT M235T was significantly associated with SaO(2) and BPs/d in AMS patients. APOB A/G was significantly associated with BPs/d in AMS and HR in CMS patients. CONCLUSION AMS and CMS share very similar genetic results for the ACE I/D and AGT M235T polymorphisms indicating that these mutations have an effect on both illnesses.
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Affiliation(s)
- Norman E Buroker
- Department of Pediatrics, University of Washington, Seattle, WA, USA.
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23
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Martin DS, Levett DZH, Grocott MPW, Montgomery HE. Variation in human performance in the hypoxic mountain environment. Exp Physiol 2010; 95:463-70. [DOI: 10.1113/expphysiol.2009.047589] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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24
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Flueck M. Myocellular limitations of human performance and their modification through genome-dependent responses at altitude. Exp Physiol 2010; 95:451-62. [DOI: 10.1113/expphysiol.2009.047605] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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25
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Koyama RG, Drager LF, Lorenzi-Filho G, Cintra FD, Pereira AC, Poyares D, Krieger JE, Castro RM, Tufik S, de Mello MT, Pedrazzoli M. Reciprocal interactions of obstructive sleep apnea and hypertension associated with ACE I/D polymorphism in males. Sleep Med 2009; 10:1107-11. [DOI: 10.1016/j.sleep.2008.12.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2008] [Revised: 12/17/2008] [Accepted: 12/17/2008] [Indexed: 10/20/2022]
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26
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The effect of angiotensin-converting enzyme genotype on acute mountain sickness and summit success in trekkers attempting the summit of Mt. Kilimanjaro (5,895 m). Eur J Appl Physiol 2008; 105:373-9. [DOI: 10.1007/s00421-008-0913-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/17/2008] [Indexed: 11/26/2022]
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27
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Abstract
An increase in hemoglobin level is seen in virtually all lowlanders who move to or train at altitude; however, studies of high-altitude native populations illustrate that this response is not necessary for successful long-term residence. Indigenous populations living at the same altitude have differences not only in hemoglobin level but also in other traits like oxygen saturation. Support for a genetic causation for differences in features of oxygen transport, namely hemoglobin levels and oxygen saturation, is derived from kindred studies among the highlander populations. Indeed, evidence from Tibet suggests that inferred genes for high oxygen saturation are associated with higher offspring survival. It may be that signaling molecules like nitric oxide and transcription factors such as hypoxia-inducible factor could act as an upstream regulator for highlander traits. However, the preponderance of data suggests that it is unlikely that one process or even a common set of processes is responsible for successful biologic adaptation shown in all three resident high-altitude populations. Future studies will require the ability to identify combinations of genetic variants with outcomes including expression levels, appropriate phenotypes, and functional responses.
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Affiliation(s)
- Kingman P Strohl
- Department of Medicine, Case Western Reserve University, Veterans Administration Medical Center, 111 J, 10701 East Boulevard, Cleveland, OH 44106, USA.
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28
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Bigham AW, Kiyamu M, León-Velarde F, Parra EJ, Rivera-Ch M, Shriver MD, Brutsaert TD. Angiotensin-converting enzyme genotype and arterial oxygen saturation at high altitude in Peruvian Quechua. High Alt Med Biol 2008; 9:167-78. [PMID: 18578648 DOI: 10.1089/ham.2007.1066] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The I-allele of the angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism has been associated with performance benefits at high altitude (HA). In n = 142 young males and females of largely Quechua origins in Peru, we evaluated 3 specific hypotheses with regard to the HA benefits of the I-allele: (1) the I-allele is associated with higher arterial oxygen saturation (Sa(O(2))) at HA, (2) the I-allele effect depends on the acclimatization state of the subjects, and (3) the putative I-allele effect on Sa(O(2)) is mediated by the isocapnic hypoxic ventilatory response (HVR, l/min(1)/% Sa(O(2))(1)). The subject participants comprised two different study groups including BLA subjects (born at low altitude) who were lifelong sea-level residents transiently exposed to hypobaric hypoxia (<24 h) and BHA subjects (born at HA) who were lifelong residents of HA. To control for the possibility of population stratification, Native American ancestry proportion (NAAP) was estimated as a covariate for each individual using a panel of 70 ancestry-informative molecular markers (AIMS). At HA, resting and exercise Sa(O(2)) was strongly associated with the ACE genotype, p = 0.008 with approximately 4% of the total variance in Sa(O(2)) attributed to ACE genotype. Moreover, I/I individuals maintained approximately 2.3 percentage point higher Sa(O(2)) compared to I/D and D/D. This I-allele effect was evident in both BLA and BHA groups, suggesting that acclimatization state has little influence on the phenotypic expression of the ACE gene. Finally, ACE genotype was not associated with the isocapnic HVR, although HVR had a strong independent effect on Sa(O(2)) (p = 0.001). This suggests that the I-allele effect on Sa(O(2)) is not mediated by the peripheral control of breathing, but rather by some other central cardiopulmonary effect of the ACE gene on the renin-angiotensin-aldosterone system (RAAS).
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Affiliation(s)
- Abigail W Bigham
- Department of Anthropology, Pennsylvania State University, University Park, Pennsylvania, USA
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29
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León-Velarde F, Mejía O. Gene Expression in Chronic High Altitude Diseases. High Alt Med Biol 2008; 9:130-9. [DOI: 10.1089/ham.2007.1077] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Fabiola León-Velarde
- Laboratorio de Fisiología Comparada, Departamento de Ciencias Biológicas y Fisiológicas, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Olga Mejía
- Laboratorio de Fisiología Comparada, Departamento de Ciencias Biológicas y Fisiológicas, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú
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Grocott M, Montgomery H. Genetophysiology: Using Genetic Strategies to Explore Hypoxic Adaptation. High Alt Med Biol 2008; 9:123-9. [DOI: 10.1089/ham.2008.1012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Mike Grocott
- UCL Institute for Human Health and Performance, London, United Kingdom
| | - Hugh Montgomery
- UCL Institute for Human Health and Performance, London, United Kingdom
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Grocott M, Richardson A, Montgomery H, Mythen M. Caudwell Xtreme Everest: a field study of human adaptation to hypoxia. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2008; 11:151. [PMID: 17672886 PMCID: PMC2206524 DOI: 10.1186/cc5921] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Caudwell Xtreme Everest (CXE) is a large healthy volunteer field study investigating human adaptation to environmental hypoxia. More than 200 individuals were studied at sea-level and in four laboratories on the trek to Everest Base Camp (5,300 m). Fifteen physicians climbed high on Everest and continued the studies as they ascended; eight of these individuals reached the summit of Everest and succeeded in sampling arterial blood at 8,400 m on their descent. Core measurements included cardiopulmonary exercise testing, neuropsychological assessment, near infra-red spectroscopy of brain and exercising muscle, blood markers and daily recording of simple physiological variables. The goal of CXE is to further our understanding of human adaptation to cellular hypoxia, a fundamental mechanism of injury in critical illness, with the aim of improving the care of critically ill patients.
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Affiliation(s)
- Mike Grocott
- Centre for Altitude, Space and Extreme Environment Medicine (CASE Medicine), UCL Institute of Human Health and Performance, Ground Floor, Charterhouse Building, UCL Archway Campus, Highgate Hill, London, N19 5LW, UK
| | - Alan Richardson
- Chelsea School, University of Brighton, Hillbrow, Denton Road, Eastbourne BN20 7SR, UK
| | - Hugh Montgomery
- Centre for Altitude, Space and Extreme Environment Medicine (CASE Medicine), UCL Institute of Human Health and Performance, Ground Floor, Charterhouse Building, UCL Archway Campus, Highgate Hill, London, N19 5LW, UK
| | - Monty Mythen
- Centre for Altitude, Space and Extreme Environment Medicine (CASE Medicine), UCL Institute of Human Health and Performance, Ground Floor, Charterhouse Building, UCL Archway Campus, Highgate Hill, London, N19 5LW, UK
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Thompson J, Raitt J, Hutchings L, Drenos F, Bjargo E, Loset A, Grocott M, Montgomery H. Angiotensin-converting enzyme genotype and successful ascent to extreme high altitude. High Alt Med Biol 2008; 8:278-85. [PMID: 18081503 DOI: 10.1089/ham.2007.1044] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Interindividual variation in acclimatization to altitude suggests a genetic component, and several candidate genes have been proposed. One such candidate is a polymorphism in the angiotensin converting enzyme (ACE) gene, where the insertion (I-allele), rather than the deletion (D-allele), of a 287 base pair sequence has been associated with lower circulating and tissue ACE activity and has a greater than normal frequency among elite endurance athletes and, in a single study, among elite high altitude mountaineers. We tested the hypothesis that the I-allele is associated with successful ascent to the extreme high altitude of 8000 m. 141 mountaineers who had participated in expeditions attempting to climb an 8000-m peak completed a questionnaire and provided a buccal swab for ACE I/D genotyping. ACE genotype was determined in 139 mountaineers. ACE genotype distribution differed significantly between those who had successfully climbed beyond 8000 m and those who had not (p = 0.003), with a relative overrepresentation of the I-allele among the successful group (0.55 vs. 0.36 in successful vs. unsuccessful, respectively). The I-allele was associated with increased maximum altitudes achieved: 8079 +/- 947 m for DDs, 8107 +/- 653 m for IDs, and 8559 +/- 565 m for IIs (p = 0.007). There was no statistical difference in ACE genotype frequency between those who climbed to over 8000 m using supplementary oxygen and those who did not (p = 0.267). This study demonstrates an association between the ACE I-allele and successful ascent to over 8000 m.
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Affiliation(s)
- Julian Thompson
- UCL Institute for Human Health and Performance, London, United Kingdom.
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Abstract
Environmental stimuli interact with common genetic variants to determine individual characteristics including physical performance: ∼80% of variation in arm eccentric flexor strength and grip strength may be genetically determined. However, many physical characteristics and physiological processes determine physical performance, and each is regulated by a large number of genes: strong genetic influences on maximum exertional oxygen uptake, heart size, lean mass, skeletal muscle growth, and bone mineral density have all been described. To date few variants strongly influencing global performance have been identified. One such is the presence (Insertion, I allele) rather than absence (Deletion, D allele) of a DNA segment in the gene encoding angiotensin-converting enzyme (ACE): The I allele has been associated with fatigue resistance/endurance, and the D-allele with strength gain.
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Affiliation(s)
- Hugh Montgomery
- Institute for Human Health and Performance, University College London, Archway Campus, London N19 5LW, United Kingdom
| | - Latif Safari
- Department of Physiology, University of Tehran, Iran
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Abstract
Altitude-related illnesses are a family of interrelated pulmonary, cerebral, hematological, and cardiovascular medical conditions associated with the diminished oxygen availability at moderate to high altitudes. The acute forms of these debilitating and potentially fatal conditions, which include acute mountain sickness (AMS), high altitude pulmonary edema (HAPE), and high altitude cerebral edema (HACE), often develop in incompletely acclimatized lowlanders shortly after ascent, whereas, the chronic conditions, such as chronic mountain sickness (CMS) and high altitude pulmonary hypertension (HAPH), usually afflict native or long-term highlanders and may reflect a loss of adaptation. Anecdotal reports of particularly susceptible people or families are frequently cited as evidence that certain individuals have an innate susceptibility (or resistance) to developing these conditions and, in recent decades, there have been a number of studies designed to characterize the physiology of individuals predisposed to these conditions, as well as to identify the specific genetic variants that contribute to this predisposition. This paper reviews the epidemiological evidence for a genetic component to the various forms of altitude-related illness, such as innate susceptibility, familial clustering, and patterns of population susceptibility, as well as the molecular evidence for specific genetic risk factors. While the evidence supports some role for genetic background in the etiology of altitude-related illness, limitations in individual studies and a general lack of corroborating research limit the conclusions that can be drawn about the extent of this contribution and the specific genes or pathways involved. The paper closes with suggestions for future work that could support and expand on previous studies, as well as provide new insights.
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Affiliation(s)
- Jim L Rupert
- School of Human Kinetics, University of British Columbia, Canada.
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Koehle MS, Wang P, Guenette JA, Rupert JL. No Association Between Variants in the ACE and Angiotensin II Receptor 1 Genes and Acute Mountain Sickness in Nepalese Pilgrims to the Janai Purnima Festival at 4380 m. High Alt Med Biol 2006; 7:281-9. [PMID: 17173513 DOI: 10.1089/ham.2006.7.281] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Koehle, Michael S., Pei Wang, Jordan A. Guenette, and Jim L. Rupert. No association between variants in the ACE and angiotensin II receptor 1 genes and acute mountain sickness in Nepalese pilgrims to the Janai Purnima Festival at 4380 m. High Alt. Med. Biol. 7:281-289, 2006.--Acute mountain sickness (AMS) causes significant morbidity among visitors to altitude. The primary contributors to developing AMS are altitude and rate of ascent; however, the substantial variation in susceptibility between individuals has led a number of investigators to propose that there may be genetic predilection to the disease. The ACE I/D polymorphism has been shown to predict performance among elite mountaineers. This study compares genotype and allele frequencies at the ACE I/D locus, two other loci in the ACE gene, and one locus in the angiotensin-2 receptor gene between individuals who did, or did not, express signs of AMS while attending a high altitude religious festival in Nepal (4380 m). Subjects (80 males, 23 females) were recruited and genotyped. All subjects were Nepalese. Forty-four of the subjects had been diagnosed with AMS by physicians at a high altitude health camp; the rest were free from altitude illness. All subjects were genotyped at polymorphic loci in the genes encoding angiotensin converting enzyme (ACE) and angiotensin II receptor type 1 gene (AGTR1). The polymorphisms examined were two single nucleotide polymorphisms (SNPs) in ACE (ACE(A-240T), dbSNP rs4291; and ACE(A2350G), dbSNP rs4343), the intronic Alu insertion in ACE (ACE I/D), and the SNP ATR(A1166C), (dbSNP rs17231380) in AGTR1d. All polymorphisms in ACE were found to be in linkage disequilibrium. No significant associations were found between AMS incidence and any of the alleles, suggesting that variants at these loci do not contribute to susceptibility to AMS in this population.
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Affiliation(s)
- Michael S Koehle
- Allan McGavin Sport Medicine Centre, Department of Family Practice, University of British Columbia, Vancouver, Canada
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Tsianos G, Woolrich-Burt L, Aitchison T, Peacock A, Watt M, Montgomery H, Watt I, Grant S. Factors affecting a climber's ability to ascend Mont Blanc. Eur J Appl Physiol 2005; 96:32-6. [PMID: 16235066 DOI: 10.1007/s00421-005-0066-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/12/2005] [Indexed: 10/25/2022]
Abstract
The aim of the study was to determine the factors affecting a climber's ability to ascend Mont Blanc using a number of variables collected at the Gouter Hut (3,817 m) before and after an attempted ascent on the Mont Blanc summit. Subjects (n=285) were tested at 3,817 m prior to their ascent of Mont Blanc. Maximum height ascended in the last 14 days was recorded. End tidal CO2, arterial oxygen saturation (SaO2), heart rate and respiratory rate were measured using a Capnograph (Nellcor Patrick NPB75). Acute mountain sickness (AMS) was assessed using the Lake Louise scoring system. Summit information is available for 216 subjects. None of the subjects who attained 4,000 m in the previous 14 days failed to reach the summit (P=0.04). Previous recent exposure to an altitude of 4,000 m resulted in faster ascent times to the summit than those who had not been above 3,000 m in the previous 14 days (4.02+/-0.6 vs. 4.46+/-0.8 h, P=0.009), higher SaO2 on arrival at the Gouter Hut on day 1 (88.6+/-5 vs. 86.3+/-6%, P=0.004) and lower AMS scores upon arrival at the Gouter Hut after the attempted ascent to the summit 2.5+/-1.8 versus 4.7+/-2.5 U (P=0.001), respectively. It is concluded that recent exposure to 4,000 m confers an advantage to those who wish to ascend a 4,800 m peak.
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Affiliation(s)
- G Tsianos
- Institute of Biomedical and Life Sciences, University of Glasgow, West Medical Building, Glasgow, G12 8QQ, UK
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Severinghaus JW. Sightings. High Alt Med Biol 2005. [DOI: 10.1089/ham.2005.6.198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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