<mods:mods xmlns:mods="http://www.loc.gov/mods/v3" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-7.xsd"><mods:titleInfo><mods:title>An Exploration of the Biology Underlying Epigenetic Clocks</mods:title></mods:titleInfo><mods:typeOfResource authority="primo">dissertations</mods:typeOfResource><mods:name type="personal"><mods:namePart>Skvir, Nicholas John</mods:namePart><mods:role><mods:roleTerm type="text">creator</mods:roleTerm></mods:role></mods:name><mods:name type="personal"><mods:namePart>Neretti, Nicola</mods:namePart><mods:role><mods:roleTerm type="text">Advisor</mods:roleTerm></mods:role></mods:name><mods:name type="personal"><mods:namePart>Wu, Zhijin</mods:namePart><mods:role><mods:roleTerm type="text">Reader</mods:roleTerm></mods:role></mods:name><mods:name type="personal"><mods:namePart>Kelsey, Karl</mods:namePart><mods:role><mods:roleTerm type="text">Reader</mods:roleTerm></mods:role></mods:name><mods:name type="personal"><mods:namePart>Istrail, Sorin</mods:namePart><mods:role><mods:roleTerm type="text">Reader</mods:roleTerm></mods:role></mods:name><mods:name type="corporate"><mods:namePart>Brown University. Center for Computational Molecular Biology</mods:namePart><mods:role><mods:roleTerm type="text">sponsor</mods:roleTerm></mods:role></mods:name><mods:originInfo><mods:copyrightDate>2022</mods:copyrightDate></mods:originInfo><mods:physicalDescription><mods:extent>xv, 82 p.</mods:extent><mods:digitalOrigin>born digital</mods:digitalOrigin></mods:physicalDescription><mods:note type="thesis">Thesis (Ph. D.)--Brown University, 2022</mods:note><mods:genre authority="aat">theses</mods:genre><mods:abstract>Abstract of An Exploration of the Biology Underlying Epigenetic Clocks&#13;
by Nicholas J. Skvir, Ph.D., Brown University, October 2022.&#13;
&#13;
Epigenetic clocks have gained popularity over the years as an accurate way to predict the age of tissues&#13;
by measuring the DNA methylation levels at specific CpG dinucleotides that have been determined to be&#13;
predictive by underlying models. Models such as these are useful in the field of aging biology for their&#13;
ability to measure changes in predicted ‘biological age’ relative to chronological age, and to observe&#13;
whether changes are present with anti-aging interventions or with the onset of disease. Despite the&#13;
widespread use of these models, it was not until very recently that specific explanations were offered to&#13;
elucidate exactly how they worked and what biological mechanisms were being measured.&#13;
&#13;
Here we reconstruct one of the original predictors and expand upon it with over one hundred&#13;
subsequently-generated clock models across multiple platforms, to create a larger, more comprehensive&#13;
library of strongly age-predictive CpG sites for pan-tissue and whole-blood-specific datasets. We use this&#13;
library to show correlation with specific genomic features from a large panel of references. We then&#13;
compare our libraries of age-predictive CpGs with subsets of CpGs used in cell mixture deconvolution (as&#13;
well as other significant lists from recent literature), to investigate whether proportional change in cell&#13;
types with age is truly the primary factor contributing to the predictions made by these models.</mods:abstract><mods:subject><mods:topic>epigenetics</mods:topic></mods:subject><mods:subject authority="fast" authorityURI="http://id.worldcat.org/fast" valueURI="http://id.worldcat.org/fast/00886570"><mods:topic>DNA--Methylation</mods:topic></mods:subject><mods:subject authority="fast" authorityURI="http://id.worldcat.org/fast" valueURI="http://id.worldcat.org/fast/00800293"><mods:topic>Aging</mods:topic></mods:subject><mods:language><mods:languageTerm authority="iso639-2b">English</mods:languageTerm></mods:language><mods:recordInfo><mods:recordContentSource authority="marcorg">RPB</mods:recordContentSource><mods:recordCreationDate encoding="iso8601">20221018</mods:recordCreationDate></mods:recordInfo></mods:mods>