Lifetime Number of Sexual Partners: A Measure of Risk-Taking Behavior or Reproductive Fitness?

Lifetime Number of Sexual Partners: A Measure of Risk-Taking Behavior or Reproductive Fitness? | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Lifetime Number of Sexual Partners: A Measure of Risk-Taking Behavior or Reproductive Fitness? Noah R. Berley, Brooke M. Huibregtse, Luke M. Evans, Michael C. Stallings This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7040623/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The number of lifetime sexual partners is a controversial metric, potentially representing both a dimension of reproductive fitness and a component of risky behavior. This study sought to disentangle the genetic architecture of this trait to determine its relationship with risk-taking and reproductive fitness constructs. We utilized summary statistics from several Genome-Wide Association Studies (GWAS) for phenotypes related to risk-taking (e.g., general risk-taking, smoking, speeding propensity) and fitness (e.g., age at first birth, number of children ever born). Using Genomic Structural Equation Modeling (GenomicSEM), we found that number of sexual partners correlated more strongly with risk-related variables than with fitness variables. A two-factor model separating risk and fitness provided a better fit to the data than a single-factor model. In this model, number of partners loaded more strongly on the risk factor (0.84) than the fitness factor (0.16), suggesting its genetic underpinnings are more closely aligned with risk-taking behaviors. Additionally, bidirectional Mendelian randomization analyses revealed evidence of causal relationships between the number of partners and other externalizing traits like speeding and problem drinking. Our findings indicate that while the relationship is complex, the genetic architecture of lifetime number of sexual partners is more closely related to general risk-taking phenotypes than to measures of reproductive fitness. Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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