Presentation Type
Oral Presentation
Category
STEM (science, technology, engineering, mathematics)
Abstract/Artist Statement
Evolutionary change is often framed primarily in terms of mutation and selection, yet this perspective overlooks a prior, testable question: which genetic changes are permitted to persist within the genome at all. This project presents a methods-driven pilot analysis that examines whether epigenetic regulation of DNA repair context constrains the retention of rare genomic variants, leaving a falsifiable signature in population-level data. The study uses de-identified, consented high-coverage Y-chromosome sequencing data and public phylogenies (e.g., FamilyTreeDNA, YFull). An explicit, a priori variant-selection rule is applied to define a class of rare lineage-discordant SNP states arising within a specified downstream phylogenetic interval. Variants are subjected to quality-control filters including coverage thresholds, exclusion of known error-prone contexts, and evaluation of persistence across descendant configurations. These variants are mapped onto phylogenetic topology and compared against early-diverging sister branches with comparable sampling depth. Under null models of technical artifact, unbiased homoplasy, or sequence-context–driven recurrence, such variants are expected to distribute broadly and unsystematically across lineages. In contrast, the constraint-based framework predicts structured clustering within a single downstream lineage and systematic absence from sister branches. These predictions are evaluated through lineage-by-variant matrices and topology-aware comparative analysis, providing explicit falsification criteria. Rather than proposing new mutational mechanisms, the framework treats long-term environmental stress as a boundary condition that may transiently relax repair canalization, expanding the space of permissible outcomes before partial re-canalization. Chromosome 2 fusion is presented as a macro-scale motivating case illustrating constraint-mediated fixation, while the Y-chromosome analysis constitutes the primary testable component. For GradCon, these observed outcome distributions are presented as a methods-focused pilot analysis motivating future experimental testing, rather than as completed mechanistic results.
Mentor Name
Jaymes Mozingo
Epigenetic Constraint Landscapes and Repair-Mediated Genome Evolution in Human Lineages
UC 326
Evolutionary change is often framed primarily in terms of mutation and selection, yet this perspective overlooks a prior, testable question: which genetic changes are permitted to persist within the genome at all. This project presents a methods-driven pilot analysis that examines whether epigenetic regulation of DNA repair context constrains the retention of rare genomic variants, leaving a falsifiable signature in population-level data. The study uses de-identified, consented high-coverage Y-chromosome sequencing data and public phylogenies (e.g., FamilyTreeDNA, YFull). An explicit, a priori variant-selection rule is applied to define a class of rare lineage-discordant SNP states arising within a specified downstream phylogenetic interval. Variants are subjected to quality-control filters including coverage thresholds, exclusion of known error-prone contexts, and evaluation of persistence across descendant configurations. These variants are mapped onto phylogenetic topology and compared against early-diverging sister branches with comparable sampling depth. Under null models of technical artifact, unbiased homoplasy, or sequence-context–driven recurrence, such variants are expected to distribute broadly and unsystematically across lineages. In contrast, the constraint-based framework predicts structured clustering within a single downstream lineage and systematic absence from sister branches. These predictions are evaluated through lineage-by-variant matrices and topology-aware comparative analysis, providing explicit falsification criteria. Rather than proposing new mutational mechanisms, the framework treats long-term environmental stress as a boundary condition that may transiently relax repair canalization, expanding the space of permissible outcomes before partial re-canalization. Chromosome 2 fusion is presented as a macro-scale motivating case illustrating constraint-mediated fixation, while the Y-chromosome analysis constitutes the primary testable component. For GradCon, these observed outcome distributions are presented as a methods-focused pilot analysis motivating future experimental testing, rather than as completed mechanistic results.