the science behind chronomics digital€¦ · introduction there is a revolution in health and...

5
The Science Behind Chronomics

Upload: others

Post on 25-May-2020

3 views

Category:

Documents


0 download

TRANSCRIPT

Page 1: The Science Behind Chronomics Digital€¦ · Introduction There is a revolution in health and wellbeing that is being driven by technological advancements in biology over the last

The Science Behind Chronomics

Page 2: The Science Behind Chronomics Digital€¦ · Introduction There is a revolution in health and wellbeing that is being driven by technological advancements in biology over the last

2

IntroductionThere is a revolution in health and wellbeing that is being driven by technological advancements in biology over the last 20 years. Research and medicine has moved from a concrete biological entity (e.g. a gene, a protein) to entire systems (i.e. all genes - genomics, all proteins - proteomics) [1]. We live in the era of the omics. Today, this technology is moving out of the lab and into the hands of individuals.

Despite the massive number of studies in the genetics fi eld, the epigenetics research community has only recently been able to access omics technologies and generate enough big data associated with their type of measurements. Recent epigenome-wide association studies (or EWAS) have identifi ed epigenetic marks with many different conditions [2]. Most studies focus on unravelling new biological insights into disease, but do not leverage that information to build accurate biomarkers. For this reason, the concept of direct-to-consumer epigenetic testing has not existed until now.

Origins of ChronomicsThe Chronomics team met while completing PhDs at the University of Cambridge, combining expertise in epigenetics, computational biology and ageing research. Our founders were pioneers in using machine learning to build epigenetic predictors of biological age. They saw the potential of this methodology to predict many more complex phenotypes, to effectively provide updated risks for developing many diseases and conditions [3, 4].

Why epigenetics?Epigenetics can be defi ned as the study of mitotically and/or meiotically stable heritable changes in gene function that cannot be explained by changes in DNA sequence [5]. Epigenetic mechanisms include DNA methylation, histone modifi cations and noncoding RNAs. Together they regulate gene expression and allow the creation of different cell types and functions starting from the same set of genes, which is needed to build complex multi-cellular organisms from a single blueprint. Unlike your genome (your DNA), which is fi xed from birth, epigenetic marks change during your lifetime upon exposure to different cues, including internal signals (e.g. hormones responses triggered by a certain mental state), external environmental factors (e.g. exposure to air pollution or chemical compounds) or life choices (e.g. type of diet, smoking, . . . ) [6]. Therefore, epigenetic information constitutes a biological layer that holistically captures the complex state of a biological system, combining multiple effects, including genetics, genetic-environmental interactions or the cellular composition of the tissue.

The Science Behind Chronomics The Science Behind Chronomics

3

Fig. 1: The diagram shows how DNA (displayed in grey) is wrapped and condensed into chromosomes with the help of many epigenetic marks, including DNA methylation (-Me groups), histone modifi cations (in the histone tails of nucleosomes, displayed as purple beads) or non-coding RNAs. These marks also help to regulate gene expression and confi gure cellular identity (e.g. Becoming a muscle cell or a skin cell) [7].

Technologies to measure DNA methylationToday we can measure DNA methylation at single base pair resolution with very highthroughput using next generation sequencing technology [13–16]. This rich, but largely unexplored, data source has enormous potential in research and in healthcare [17, 18]. The most widely used single base resolution methods currently rely on a chemical reaction step called bisulphite conversion. Treatment of DNA with sodium bisulphite enables cytosines to be differentiated based upon whether they are methylated or unmethylated. Methylated cytosines remain unchanged, whereas unmethylated cytosines are converted into the base uracil (U) and then, after PCR amplifi cation (with A,C,G,T deoxynucleotides), into thymine (T) [19]. This amplifi ed library (or DNA) pool can then be sequenced and the data processed to map methylation patterns.

Choosing the right tissueDifferent cell types have different epigenomes. This allows them, starting with the same genetic code, to express different subsets of genes and specialise in their function, such as transmitting nerve impulses in the case of neurons or secreting antibodies in the case of B cells. Therefore, since different tissues are composed of different cell types, they show different profi les when assessed for their DNA methylation patterns [20].

At Chronomics we use saliva as our tissue of choice. Saliva represents a very attractive source for the next generation of biomarker studies [21] and it contains a mix of buccal epithelial cells and leukocytes, from which DNA can be successfully extracted [22]. Using saliva as our main DNA source has many associated benefi ts, including:

• Ease-of-use and non-invasive sampling process.

• DNA methylation profi ling in saliva samples is becoming increasingly common and has proven useful in studies looking at many different diseases and conditions, such as Parkinson’s [23], respiratory allergy [24], attention-defi cit/hyperactivity disorder [25], head and neck cancer [26] and obesity [27, 28]. This allows for the direct translation of many discoveries from the literature into our platform.

• DNA methylation profi les of saliva are correlated with those in blood (R2 = 0.97) and brain (R2 = 0.86) [29], which makes it a fantastic surrogate tissue to capture effects associated with many complex traits [30–32].

• Buccal cells seem to show more stable DNA methylation profi les in longitudinal studies when compared with other tissues [33], which will be a core component of the Chronomics’ repeatable DNA test.

Building predictors from DNA methylationIn 2013 Professor Steve Horvath of UCLA showed that biological age can be accurately predicted across different tissues using DNA methylation data [46]. In addition, he and others have shown that this model is affected by disease states associated with environmental and lifestyle factors [34–56].

Aside from age, there are many more successful examples of phenotypes or biological conditions for which predictors have been built using DNA methylation. These include many types of cancer [5], coronary heart disease [57], type 2 diabetes [58], BMI [59] smoking exposure [60], alcohol consumption [61], postpartum depression [62] or gestational age [63, 64]. The potential in the medical fi eld is enormous, however the focus of Chronomics is on prevention and wellbeing.

The power of these predictors is that they behave like updated risk scores. For example, the incidence of obesity-associated cancers could be predicted using an obesityassociated DNA methylation signature that measures the adiposity history of the individual, irrespective of the actual BMI of the individual at the time of assessment [5]. Furthermore, lung cancer risk prediction can be improved when including some DNA methylation markers associated with smoking exposure [65], even after adjusting for current smoking status and duration [66].

DNA methylation has all the ideal characteristics to build robust predictors from machine learning:

It is a biologically stable and technically reproducible marker that can integrate genetic and non-genetic effects. Currently, most risk models only include epidemiological factors and they normally do not enable differentiation of individuals with good and poor prognosis. DNA methylation effectively captures an individual interaction at the molecular level with environmental factors such as stress, nutrition, smoking and/or absence of physical exercise, which are key components of multivariable risk algorithms.

Chronomics’ actionable epigenetic indicatorsThe focus of Chronomics is on health, wellbeing, and prevention of age and lifestyle related diseases by monitoring and reducing risk factors. We are non-diagnostic, but we show our users how to avoid illness with actionable indicators for health and environmental impact that can be improved by positive life changes.

Certain lifestyle interventions, such as exercise [67, 68], quitting smoking [69, 70] or drinking [71, yoga classes [72], dietary changes [73, 74] or weight loss [75], can reverse specifi c sets of epigenetic markers associated with ill health.

We are pioneering a new era of DNA testing powered by epigenetic predictors, becoming the fi rst company in the world to translate the predictive power of DNA methylation into benefi ts for the health and wellbeing of our society.

What is DNA methylation? DNA methylation is the addition of a methyl (CH3) group to DNA by DNA methyltransferase (DNMT) enzymes. In humans, this mostly occurs on cytosine bases where the cytosine is followed by a guanine base (commonly referred to as a CpG site), of which there are more than 28 million in the human genome [7]. In a given DNA strand of a given cell, the methylation readout of each one of these CpG sites is a binary variable: the site is methylated or not. However, when a sample is taken from a tissue many cells are analysed at the same time. DNA methylation at a CpG site is therefore normally expressed as a percentage, which approximately refl ects how many cells in that tissue are methylated at that genomic location [8, 9]. DNA methylation has been shown to be infl uenced by both genetics, the environment, and health [10, 12].

Page 3: The Science Behind Chronomics Digital€¦ · Introduction There is a revolution in health and wellbeing that is being driven by technological advancements in biology over the last

The Science Behind Chronomics The Science Behind Chronomics

References:1. Gavin Kelsey, Oliver Stegle, and Wolf Reik. Single-cell epigenomics: Recording the past and predicting the future.

Science, 358(6359):69–75, 2017.

2. James M Flanagan. Epigenome-wide association studies (EWAS): past, present, and future. In Cancer Epigenetics, pages

51–63. Springer, 2015.

3. Andrew E Teschendorff and Caroline L Relton. Statistical and integrative system-level analysis of DNA methylation data.

Nature Reviews Genetics, 19(3):129, 2018.

4. Martin Widschwendter, Allison Jones, Iona Evans, Daniel Reisel, Joakim Dillner, Karin Sundström, Ewout W. Steyerberg,

Yvonne Vergouwe, Odette Wegwarth, Felix G. Rebitschek, Uwe Siebert, Gaby Sroczynski, Inez D. de Beaufort, Ineke Bolt,

David Cibula, Michal Zikan, Line Bjørge, Nicoletta Colombo, Nadia Harbeck, Frank Dud-bridge, Anne-Marie Tasse, Bartha

M. Knoppers, Yann Joly, Andrew E. Teschendorff, and Nora Pashayan. Epigenome-based cancer risk prediction: rationale,

opportunities and challenges. Nature Reviews Clinical Oncology, 15:292–309, 2018.

5. Vincenzo EA Russo, Robert A Martienssen, and Arthur D Riggs. Epigenetic mechanisms of gene regulation.

Cold Spring Harbor Laboratory Press, 1996.

6. Robert Feil and Mario F Fraga. Epigenetics and the environment: emerging patterns and implications.

Nature Reviews Genetics, 13(2):97, 2012.

7. Keith D Robertson. DNA methylation and human disease. Nature Reviews Genetics, 6 (8):597, 2005.

8. Peter W Laird. Principles and challenges of genome-wide DNA methylation analysis. Nature Reviews Genetics, 11(3):191, 2010.

9. Andrew E Teschendorff and Shijie C Zheng. Cell-type deconvolution in epigenome-wide association studies: a review

and recommendations. Epigenomics, 9(5):757–768, 2017.

10. Christof Angermueller, Heather J Lee, Wolf Reik, and Oliver Stegle. Deepcpg: accurate prediction of single-cell DNA

methylation states using deep learning. Genome biology, 18(1):67, 2017.

11. Jenny Van Dongen, Michel G Nivard, Gonneke Willemsen, Jouke-Jan Hottenga, Quinta Helmer, Conor V Dolan, Erik A Ehli,

Gareth E Davies, Maarten Van Iterson, Charles E Breeze, et al. Genetic and environmental in uences interact with age and sex in

shaping the human methylome. Nature communications, 7:11115, 2016.

12. Arthur C Rand, Miten Jain, Jordan M Eizenga, Audrey Musselman-Brown, Hugh E Olsen, Mark Akeson, and Benedict Paten.

Mapping DNA methylation with high- throughput nanopore sequencing. Nature methods, 14(4):411, 2017.

13. Marina Bibikova, Zhenwu Lin, Lixin Zhou, Eugene Chudin, Eliza Wickham Garcia, Bonnie Wu, Dennis Doucet, Neal J Thomas,

Yunhua Wang, Ekkehard Vollmer, et al. High-throughput DNA methylation pro ling using universal bead arrays. Genome

research, 16(3):383–393, 2006.

14. Ning Li, Mingzhi Ye, Yingrui Li, Zhixiang Yan, Lee M Butcher, Jihua Sun, Xu Han, Quan Chen, Jun Wang, et al. Whole genome

DNA methylation analysis based on high throughput sequencing technology. Methods, 52(3):203–212, 2010.

15 Fiona Allum, Xiaojian Shao, Frédéric Guénard, Marie-Michelle Simon, Stephan Busche, Maxime Caron, John Lambourne,

Julie Lessard, Karolina Tandre, Åsa K Hedman, et al. Characterization of functional methylomes by next-generation capture

sequencing identi es novel disease-associated variants. Nature communications, 6: 7211, 2015.

16. Colleen M McBride and Laura M Koehly. Imagining roles for epigenetics in health promotion research. Journal of behavioral

medicine, 40(2):229–238, 2017.

17. Mahmood Rasool, Arif Malik, Muhammad Imran Naseer, Abdul Manan, Sha- keel Ahmed Ansari, Irshad Begum, Mahmood

Husain Qazi, Peter Natesan Pushparaj, Adel M Abuzenadah, Mohammed Hussein Al-Qahtani, et al. The role of epigenetics in

personalized medicine: challenges and opportunities. BMC medical genomics, 8(1):S5, 2015.

4 5

18. Sascha Tierling, Beate Schmitt, and Jörn Walter. Comprehensive evaluation of commercial bisul te-based DNA methylation

kits and development of an alternative protocol with improved conversion performance. Genetics & epigenetics,

10:1179237X18766097, 2018.

19. Michael J Ziller, Hongcang Gu, Fabian Müller, Julie Donaghey, Linus T-Y Tsai, Oliver Kohlbacher, Philip L De Jager, Evan D

Rosen, David A Bennett, Bradley E Bernstein, et al. Charting a dynamic DNA methylation landscape of the human genome.

Nature, 500(7463):477, 2013.

20. Sabine AS Langie, Matthieu Moisse, Ken Declerck, Gudrun Koppen, Lode Godderis, Wim Vanden Berghe, Stacy Drury,

and Patrick De Boever. Salivary DNA methylation profi ling: aspects to consider for biomarker identifi cation. Basic & clinical

pharmacology & toxicology, 121(S3):93–101, 2017.

21. Alicia K Smith, Varun Kilaru, Torsten Klengel, Kristina B Mercer, Bekh Bradley, Karen N Conneely, Kerry J Ressler, and Elisabeth

B Binder. DNA extracted from saliva for methylation studies of psychiatric traits: evidence tissue specifi city and relatedness to

brain. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics, 168(1):36–44, 2015.

22. Yu-Hsuan Chuang, Kimberly C Paul, Jeff M Bronstein, Yvette Bordelon, Steve Horvath, and Beate Ritz. Parkinson’s disease is

associated with DNA methylation levels in human blood and saliva. Genome medicine, 9(1):76, 2017.

23. Sabine AS Langie, Katarzyna Szarc vel Szic, Ken Declerck, Sophie Traen, Gudrun Koppen, Guy Van Camp, Greet Schoeters,

Wim Vanden Berghe, and Patrick De Boever. Whole-genome saliva and blood DNA methylation profi ling in individuals with a

respiratory allergy. PloS one, 11(3):e0151109, 2016.

24. Beth Wilmot, Rebecca Fry, Lisa Smeester, Erica D Musser, Jonathan Mill, and Joel T Nigg. Methylomic analysis of salivary DNA

in childhood ADHD identities altered DNA methylation in vipr2. Journal of Child Psychology and Psychiatry, 57(2):152–160,

2016.

25. Yenkai Lim, Yunxia Wan, Dimitrios Vagenas, Dmitry A Ovchinnikov, Chris FL Perry, Melissa J Davis, and Chamindie Punyadeera.

Salivary DNA methylation panel to diagnose hpv-positive and HPV-negative head and neck cancers. BMC cancer, 16(1):749, 2016.

26. Kathryn Tully Oelsner, Yan Guo, Sophie Bao-Chieu To, Amy L Non, and Shari L Barkin. Maternal BMI as a predictor of

methylation of obesity-related genes in saliva samples from preschool-age hispanic children at-risk for obesity. BMC genomics,

18 (1):57, 2017.

27. Trine B Rounge, Christian M Page, Maija Lepistö, Pekka Ellonen, Bettina K Andreassen, and Elisabete Weiderpass.

Genome-wide DNA methylation in saliva and body size of adolescent girls. Epigenomics, 8(11):1495–1505, 2016.

28. Patricia Braun, Marie Hafner, Yasunori Nagahama, Benjamin Hing, Melissa McKane, Andrew Grossbach, Matthew Howard,

Hiroto Kawasaki, James Potash, and Gen Shinozaki. Genome-wide DNA methylation comparison between live human brain

and peripheral tissues within individuals. European Neuropsychopharmacology, 27:S506, 2017.

29. Nicklas Heine Staunstrup, Anna Starnawska, Mette Nyegaard, Anders Lade Nielsen, Anders Børglum, and Ole Mors.

Saliva as a blood alternative for genome-wide DNA methylation profi ling by methylated DNA immunoprecipitation (medip)

sequencing. Epigenomes, 1(3):14, 2017.

30. Robert Lowe, Carolina Gemma, Huriya Beyan, Mohammed I Hawa, Alexandra Bazeos, R David Leslie, Alexandre Montpetit,

Vardhman K Rakyan, and Sreeram V Ram- agopalan. Buccals are likely to be a more informative surrogate tissue than blood for

epigenome-wide association studies. Epigenetics, 8(4):445–454, 2013.

31. Marie Forest, Kieran J O’Donnell, Greg Voisin, Helene Gaudreau, Julia L MacIsaac, Lisa M McEwen, Patricia P Silveira, Meir

Steiner, Michael S Kobor, Michael J Meaney, et al. Agreement in DNA methylation levels from the illumina 450k array across

batches, tissues, and time. Epigenetics, 13(1):19–32, 2018.

32. Steve Horvath. DNA methylation age of human tissues and cell types. Genome biology, 14(10):3156, 2013.

33. Marco P Boks, Hans C van Mierlo, Bart PF Rutten, Timothy RDJ Radstake, Lot De Witte, Elbert Geuze, Steve Horvath, Leonard C

Schalkwyk, Christiaan H Vinkers, Jasper CA Broen, et al. Longitudinal changes of telomere length and epigenetic age related to

traumatic stress and posttraumatic stress disorder. Psychoneuroendocrinology, 51:506–512, 2015.

Page 4: The Science Behind Chronomics Digital€¦ · Introduction There is a revolution in health and wellbeing that is being driven by technological advancements in biology over the last

6 7

34. Steve Horvath, Wiebke Erhart, Mario Brosch, Ole Ammerpohl, Witigo von Schönfels, Markus Ahrens, Nils Heits, Jordana T Bell,

Pei-Chien Tsai, Tim D Spector, et al. Obesity accelerates epigenetic aging of human liver. Proceedings of the National Academy

of Sciences, 111(43):15538–15543, 2014.

35. Riccardo E Marioni, Sonia Shah, Allan F McRae, Stuart J Ritchie, Graciela Muniz- Terrera, Sarah E Harris, Jude Gibson, Paul

Redmond, Simon R Cox, Alison Pattie, et al. The epigenetic clock is correlated with physical and cognitive tness in the lothian

birth cohort 1936. International journal of epidemiology, 44(4):1388–1396, 2015.

36. Steve Horvath, Paolo Garagnani, Maria Giulia Bacalini, Chiara Pirazzini, Stefano Salvioli, Davide Gentilini, Anna Maria Di

Blasio, Cristina Giuliani, Spencer Tung, Harry V Vinters, et al. Accelerated epigenetic aging in down syndrome. Aging cell,

14 (3):491–495, 2015.

37. Tammy M Rickabaugh, Ruth M Baxter, Mary Sehl, Janet S Sinsheimer, Patricia M Hultin, Lance E Hultin, Austin Quach, Otoniel

Martínez-Maza, Steve Horvath, Eric Vilain, et al. Acceleration of age-associated methylation patterns in HIV-1-infected adults.

PloS one, 10(3):e0119201, 2015.

38. Richard F Walker, Jia Sophie Liu, Brock A Peters, Beate R Ritz, Timothy Wu, Roel A Ophoff, and Steve Horvath. Epigenetic age

analysis of children who seem to evade aging. Aging (Albany NY), 7(5):334, 2015.

39. Morgan E Levine, H Dean Hosgood, Brian Chen, Devin Absher, Themistocles Assimes, and Steve Horvath. DNA methylation

age of blood predicts future onset of lung cancer in the women’s health initiative. Aging (Albany NY), 7(9):690, 2015.

40. Andrew J Simpkin, Gibran Hemani, Matthew Suderman, Tom R Gaunt, Oliver Lyttleton, Wendy L Mcardle, Susan M Ring,

Gemma C Sharp, Kate Tilling, Steve Horvath, et al. Prenatal and early life infl uences on epigenetic age in children: a study

of mother–offspring pairs from two cohort studies. Human molecular genetics, 25(1):191–201, 2015.

41. Steve Horvath and Beate R Ritz. Increased epigenetic age and granulocyte counts in the blood of parkinson’s disease patients.

Aging (Albany NY), 7(12):1130, 2015.

42. Steve Horvath, Chiara Pirazzini, Maria Giulia Bacalini, Davide Gentilini, Anna Maria Di Blasio, Massimo Delledonne,

Daniela Mari, Beatrice Arosio, Daniela Monti, Giuseppe Passarino, et al. Decreased epigenetic age of pbmcs from italian

semi- supercentenarians and their offspring. Aging (Albany NY), 7(12):1159, 2015.

43. Morgan E Levine, Ake T Lu, David A Bennett, and Steve Horvath. Epigenetic age of the pre-frontal cortex is associated with

neuritic plaques, amyloid load, and alzheimer’s disease related cognitive functioning. Aging (Albany NY), 7(12):1198, 2015.

44. Morgan E Levine, Ake T Lu, Brian H Chen, Dena G Hernandez, Andrew B Singleton, Luigi Ferrucci, Stefania Bandinelli, Elias

Salfati, JoAnn E Manson, Austin Quach, et al. Menopause accelerates biological aging. Proceedings of the National Academy

of Sciences, 113(33):9327–9332, 2016.

45. Steve Horvath, Peter Langfelder, Seung Kwak, Jeff Aaronson, Jim Rosinski, Thomas F Vogt, Marika Eszes, Richard LM Faull,

Maurice A Curtis, Henry J Waldvogel, et al. Huntington’s disease accelerates epigenetic aging of human brain and disrupts DNA

methylation levels. Aging (Albany NY), 8(7):1485, 2016.

46. Steve Horvath, Michael Gurven, Morgan E Levine, Benjamin C Trumble, Hillard Kaplan, Hooman Allayee, Beate R Ritz, Brian

Chen, Ake T Lu, Tammy M Rickabaugh, et al. An epigenetic clock analysis of race/ethnicity, sex, and coronary heart disease.

Genome biology, 17(1):171, 2016.

47. Laura Vidal-Bralo, Yolanda Lopez-Golan, Antonio Mera-Varela, Ignacio Rego-Perez, Steve Horvath, Yuhua Zhang, Álvaro del

Real, Guangju Zhai, Francisco J Blanco, Jose A Riancho, et al. Speci c premature epigenetic aging of cartilage in osteoarthritis.

Aging (Albany NY), 8(9):2222, 2016.

48. Judith E Carroll, Michael R Irwin, Morgan Levine, Teresa E Seeman, Devin Absher, Themistocles Assimes, and Steve Horvath.

Epigenetic aging and immune senescence in women with insomnia symptoms: fi ndings from the women’s health initiative study.

Biological psychiatry, 81(2):136–144, 2017.

49. Andrew J Simpkin, Laura D Howe, Kate Tilling, Tom R Gaunt, Oliver Lyttleton, Wendy L McArdle, Susan M Ring, Steve

Horvath, George Davey Smith, and Caroline L Relton. The epigenetic clock and physical development during childhood and

adolescence: longitudinal analysis from a UK birth cohort. International journal of epidemiology, 46(2):549–558, 2017.

50. Austin Quach, Morgan E Levine, Toshiko Tanaka, Ake T Lu, Brian H Chen, Luigi Ferrucci, Beate Ritz, Stefania Bandinelli, Marian

L Neuhouser, Jeannette M Beasley, et al. Epigenetic clock analysis of diet, exercise, education, and lifestyle factors. Aging

(Albany NY), 9(2):419, 2017.

51. Srikant Ambatipudi, Steve Horvath, Flavie Perrier, Cyrille Cuenin, Hector Hernandez- Vargas, Florence Le Calvez-Kelm,

Geoffroy Durand, Graham Byrnes, Pietro Ferrari, Liacine Bouaoun, et al. DNA methylome analysis identities accelerated

epigenetics

52. References 25 ageing associated with postmenopausal breast cancer susceptibility. European Journal of Cancer,

75:299–307, 2017.

53. Anna Maierhofer, Julia Flunkert, Junko Oshima, George M Martin, Thomas Haaf, and Steve Horvath. Accelerated epigenetic

aging in werner syndrome. Aging (Albany NY), 9(4):1143, 2017.

54. Alexey Kozlenkov, Andrew E Jaffe, Alisa Timashpolsky, Pasha Apontes, Sergei Rud- chenko, Mihaela Barbu, William Byne,

Yasmin L Hurd, Steve Horvath, and Stella Dracheva. DNA methylation pro ling of human prefrontal cortex neurons in heroin

users shows signifi cant difference between genomic contexts of hyper-and hypomethylation and a younger epigenetic age.

Genes, 8(6):152, 2017.

55. Friedrich Stölzel, Mario Brosch, Steve Horvath, Michael Kramer, Christian Thiede, Malte von Bonin, Ole Ammerpohl,

Moritz Middeke, Johannes Schetelig, Gerhard Ehninger, et al. Dynamics of epigenetic age following hematopoietic stem cell

transplantation. haematologica, 102(8):e321–e323, 2017.

56. Alexandra M Binder, Camila Corvalan, Verónica Mericq, Ana Pereira, José Luis Santos, Steve Horvath, John Shepherd,

and Karin B Michels. Faster ticking rate of the epigenetic clock is associated with faster pubertal development in girls.

Epigenetics, 13(1):85–94, 2018.

57. Marguerite R Irvin, Stella Aslibekyan, Anh Do, Degui Zhi, Bertha Hidalgo, Steven A Claas, Vinodh Srinivasasainagendra,

Steve Horvath, Hemant K Tiwari, Devin M Absher, et al. Metabolic and in ammatory biomarkers are associated with epigenetic

aging acceleration estimates in the goldn study. Clinical epigenetics, 10(1):56, 2018.

58. Meeshanthini V Dogan, Isabella M Grumbach, Jacob J Michaelson, and Robert A Philibert. Integrated genetic and epigenetic

prediction of coronary heart disease in the framingham heart study. PloS one, 13(1):e0190549, 2018.

59. Tasnim Dayeh, Tiinamaija Tuomi, Peter Almgren, Alexander Per lyev, Per-Anders Jansson, Vanessa D de Mello, Jussi Pihlajamäki,

Allan Vaag, Leif Groop, Emma Nilsson, et al. Dna methylation of loci within abcg1 and phospho1 in blood DNA is associated

with future type 2 diabetes risk. Epigenetics, 11(7):482–488, 2016.

60. Sonia Shah, Marc J Bonder, Riccardo E Marioni, Zhihong Zhu, Allan F McRae, Alexandra Zhernakova, Sarah E Harris,

Dave Liewald, Anjali K Henders, Michael M Mendelson, et al. Improving phenotypic prediction by combining genetic and

epigenetic associations. The American Journal of Human Genetics, 97(1):75–85, 2015.

61. Yan Zhang, Ben Schöttker, Ines Florath, Christian Stock, Katja Butterbach, Bernd Holleczek, Ute Mons, and Hermann Brenner.

Smoking-associated DNA methylation biomarkers and their predictive value for all-cause and cardiovascular mortality.

Environmental health perspectives, 124(1):67, 2016.

62. C Liu, RE Marioni, Å K Hedman, L Pfeiffer, PC Tsai, LM Reynolds, AC Just, Q Duan, CG Boer, T Tanaka, et al. A DNA methylation

biomarker of alcohol consumption. Molecular psychiatry, 2016.

63. Jerry Guintivano, Michal Arad, Todd D Gould, Jennifer L Payne, and ZA Kaminsky. Antenatal prediction of postpartum depression with

blood DNA methylation biomarkers. Molecular psychiatry, 19(5):560, 2014

64. Anna K Knight, Jeffrey M Craig, Christiane Theda, Marie Bækvad-Hansen, Jonas Bybjerg-Grauholm, Christine S Hansen, Mads

V Hollegaard, David M Hougaard, Preben B Mortensen, Shantel M Weinsheimer, et al. An epigenetic clock for gestational age

at birth based on blood methylation data. Genome biology, 17(1):206, 2016.

34. Steve Horvath, Wiebke Erhart, Mario Brosch, Ole Ammerpohl, Witigo von Schönfels, Markus Ahrens, Nils Heits, Jordana T Bell,

Pei-Chien Tsai, Tim D Spector, et al. Obesity accelerates epigenetic aging of human liver. Proceedings of the National Academy

35. Riccardo E Marioni, Sonia Shah, Allan F McRae, Stuart J Ritchie, Graciela Muniz- Terrera, Sarah E Harris, Jude Gibson, Paul

Redmond, Simon R Cox, Alison Pattie, et al. The epigenetic clock is correlated with physical and cognitive tness in the lothian

Pei-Chien Tsai, Tim D Spector, et al. Obesity accelerates epigenetic aging of human liver. Proceedings of the National Academy

of Sciences, 111(43):15538–15543, 2014.

35. Riccardo E Marioni, Sonia Shah, Allan F McRae, Stuart J Ritchie, Graciela Muniz- Terrera, Sarah E Harris, Jude Gibson, Paul

Redmond, Simon R Cox, Alison Pattie, et al. The epigenetic clock is correlated with physical and cognitive tness in the lothian

birth cohort 1936. International journal of epidemiology, 44(4):1388–1396, 2015.

34. Steve Horvath, Wiebke Erhart, Mario Brosch, Ole Ammerpohl, Witigo von Schönfels, Markus Ahrens, Nils Heits, Jordana T Bell, 34. Steve Horvath, Wiebke Erhart, Mario Brosch, Ole Ammerpohl, Witigo von Schönfels, Markus Ahrens, Nils Heits, Jordana T Bell,

Pei-Chien Tsai, Tim D Spector, et al. Obesity accelerates epigenetic aging of human liver. Proceedings of the National Academy

birth cohort 1936. International journal of epidemiology, 44(4):1388–1396, 2015.

Redmond, Simon R Cox, Alison Pattie, et al. The epigenetic clock is correlated with physical and cognitive tness in the lothian

birth cohort 1936. International journal of epidemiology, 44(4):1388–1396, 2015.

34. Steve Horvath, Wiebke Erhart, Mario Brosch, Ole Ammerpohl, Witigo von Schönfels, Markus Ahrens, Nils Heits, Jordana T Bell, 34. Steve Horvath, Wiebke Erhart, Mario Brosch, Ole Ammerpohl, Witigo von Schönfels, Markus Ahrens, Nils Heits, Jordana T Bell,

The Science Behind Chronomics The Science Behind Chronomics

63. Jerry Guintivano, Michal Arad, Todd D Gould, Jennifer L Payne, and ZA Kaminsky. Antenatal prediction of postpartum depression with 63. Jerry Guintivano, Michal Arad, Todd D Gould, Jennifer L Payne, and ZA Kaminsky. Antenatal prediction of postpartum depression with

64. Anna K Knight, Jeffrey M Craig, Christiane Theda, Marie Bækvad-Hansen, Jonas Bybjerg-Grauholm, Christine S Hansen, Mads

V Hollegaard, David M Hougaard, Preben B Mortensen, Shantel M Weinsheimer, et al. An epigenetic clock for gestational age

epigenetic associations. The American Journal of Human Genetics, 97(1):75–85, 2015.

61. Yan Zhang, Ben Schöttker, Ines Florath, Christian Stock, Katja Butterbach, Bernd Holleczek, Ute Mons, and Hermann Brenner.

Smoking-associated DNA methylation biomarkers and their predictive value for all-cause and cardiovascular mortality.

Environmental health perspectives, 124(1):67, 2016.

62. C Liu, RE Marioni, Å K Hedman, L Pfeiffer, PC Tsai, LM Reynolds, AC Just, Q Duan, CG Boer, T Tanaka, et al. A DNA methylation

biomarker of alcohol consumption. Molecular psychiatry, 2016.

63. Jerry Guintivano, Michal Arad, Todd D Gould, Jennifer L Payne, and ZA Kaminsky. Antenatal prediction of postpartum depression with

blood DNA methylation biomarkers. Molecular psychiatry, 19(5):560, 2014

64. Anna K Knight, Jeffrey M Craig, Christiane Theda, Marie Bækvad-Hansen, Jonas Bybjerg-Grauholm, Christine S Hansen, Mads

V Hollegaard, David M Hougaard, Preben B Mortensen, Shantel M Weinsheimer, et al. An epigenetic clock for gestational age

at birth based on blood methylation data. Genome biology, 17(1):206, 2016.

Epigenetic aging and immune senescence in women with insomnia symptoms: fi ndings from the women’s health initiative study. 63. Jerry Guintivano, Michal Arad, Todd D Gould, Jennifer L Payne, and ZA Kaminsky. Antenatal prediction of postpartum depression with

blood DNA methylation biomarkers. Molecular psychiatry, 19(5):560, 2014

64. Anna K Knight, Jeffrey M Craig, Christiane Theda, Marie Bækvad-Hansen, Jonas Bybjerg-Grauholm, Christine S Hansen, Mads

V Hollegaard, David M Hougaard, Preben B Mortensen, Shantel M Weinsheimer, et al. An epigenetic clock for gestational age

at birth based on blood methylation data. Genome biology, 17(1):206, 2016.

63. Jerry Guintivano, Michal Arad, Todd D Gould, Jennifer L Payne, and ZA Kaminsky. Antenatal prediction of postpartum depression with

64. Anna K Knight, Jeffrey M Craig, Christiane Theda, Marie Bækvad-Hansen, Jonas Bybjerg-Grauholm, Christine S Hansen, Mads

V Hollegaard, David M Hougaard, Preben B Mortensen, Shantel M Weinsheimer, et al. An epigenetic clock for gestational age

63. Jerry Guintivano, Michal Arad, Todd D Gould, Jennifer L Payne, and ZA Kaminsky. Antenatal prediction of postpartum depression with

biomarker of alcohol consumption. Molecular psychiatry, 2016.

63. Jerry Guintivano, Michal Arad, Todd D Gould, Jennifer L Payne, and ZA Kaminsky. Antenatal prediction of postpartum depression with

blood DNA methylation biomarkers. Molecular psychiatry, 19(5):560, 2014

64. Anna K Knight, Jeffrey M Craig, Christiane Theda, Marie Bækvad-Hansen, Jonas Bybjerg-Grauholm, Christine S Hansen, Mads

V Hollegaard, David M Hougaard, Preben B Mortensen, Shantel M Weinsheimer, et al. An epigenetic clock for gestational age

at birth based on blood methylation data. Genome biology, 17(1):206, 2016.

biomarker of alcohol consumption. Molecular psychiatry, 2016.

epigenetic associations. The American Journal of Human Genetics, 97(1):75–85, 2015.

at birth based on blood methylation data. Genome biology, 17(1):206, 2016.

48. Judith E Carroll, Michael R Irwin, Morgan Levine, Teresa E Seeman, Devin Absher, Themistocles Assimes, and Steve Horvath.

Page 5: The Science Behind Chronomics Digital€¦ · Introduction There is a revolution in health and wellbeing that is being driven by technological advancements in biology over the last

The Science Behind Chronomics

65. Jon Bohlin, Siri Eldevik Håberg, Per Magnus, Sarah E Reese, Håkon K Gjessing, Maria Christine Magnus, Christine Louise Parr,

CM Page, Stephanie J London, and Wenche Nystad. Prediction of gestational age based on genome-wide differentially methylated

regions. Genome biology, 17(1):207, 2016.

66. Laura Baglietto, Erica Ponzi, Philip Haycock, Allison Hodge, Manuela Bianca As- summa, Chol-Hee Jung, Jessica Chung,

Francesca Fasanelli, Florence Guida, Gianluca Campanella, et al. DNA methylation changes measured in pre-diagnostic

peripheral blood samples are associated with smoking and lung cancer risk. International journal of cancer,

140(1):50–61, 2017.

67. Maléne E Lindholm, Francesco Marabita, David Gomez-Cabrero, Helene Rundqvist, Tomas J Ekström, Jesper Tegnér, and Carl

Johan Sundberg. An integrative analysis reveals coordinated reprogramming of the epigenome and the transcriptome in human

skeletal muscle after training. Epigenetics, 9(12):1557–1569, 2014.

68. Magdalena Spólnicka, Ewelina Pos piech, Jakub Grzegorz Adamczyk, Ana Freire- Aradas, Beata Pepłon ska, Renata Zbiec

-Piekarska, Zanetta Makowska, Anna Pieta, Maria Victoria Lareu, Christopher Phillips, et al. Modifi ed aging of elite athletes

revealed by analysis of epigenetic age markers. Aging (Albany NY), 10(2):241, 2018.

69. Loukia G Tsaprouni, Tsun-Po Yang, Jordana Bell, Katherine J Dick, Stavroula Kanoni, James Nisbet, Ana Viñuela, Elin

Grundberg, Christopher P Nelson, Eshwar Meduri, et al. Cigarette smoking reduces DNA methylation levels at multiple genomic

loci but the effect is partially reversible upon cessation. Epigenetics, 9(10):1382–1396, 2014.

70. Florence Guida, Torkjel M Sandanger, Raphaële Castagné, Gianluca Campanella, Silvia Polidoro, Domenico Palli, Vittorio

Krogh, Rosario Tumino, Carlotta Sacerdote, Salvatore Panico, et al. Dynamics of smoking-induced genome-wide methylation

changes with time since smoking cessation. Human molecular genetics, 24(8):2349– 2359, 2015.

71. Christof Brückmann, Sumaiya A Islam, Julia L MacIsaac, Alexander M Morin, Kathrin N Karle, Adriana Santo, Richard Wüst,

Immanuel Lang, Anil Batra, Michael S Kobor, et al. Dna methylation signatures of chronic alcohol dependence in puri ed cd3+

t-cells of patients undergoing alcohol treatment. Scientifi c reports, 7(1):6605, 2017.

72. KN Harkess, J Ryan, PH Delfabbro, and Sarah Cohen-Woods. Preliminary indications of the effect of a brief yoga intervention

on markers of in ammation and DNA methylation in chronically stressed women. Translational psychiatry, 6(11):e965, 2016.

73. Dieuwertje EG Kok, Rosalie AM Dhonukshe-Rutten, Carolien Lute, Sandra G Heil, André G Uitterlinden, Nathalie van der

Velde, Joyce BJ van Meurs, Natasja M van Schoor, Guido JEJ Hooiveld, Lisette CPGM de Groot, et al. The effects of long-term

daily folic acid and vitamin b 12 supplementation on genome-wide DNA methylation in elderly subjects. Clinical epigenetics,

7(1):121, 2015.

74. Faiza Noreen, Martin Röösli, Pawel Gaj, Jakub Pietrzak, Stefan Weis, Patric Urfer, Jaroslaw Regula, Primo Schär, and Kaspar

Truninger. Modulation of age-and cancer-associated DNA methylation change in the healthy colon by aspirin and lifestyle.

JNCI: Journal of the National Cancer Institute, 106(7):dju161, 2014.

75. Lucia Aronica, A Joan Levine, Kevin Brennan, Jeffrey Mi, Christopher Gardner, Robert W Haile,

and Megan P Hitchins. A systematic review of studies of DNA methylation in the context of a

weight loss intervention. Epigenomics, 9(5):769–787, 2017.

Making the unseen [email protected]