Speaker: Sam Trejo

Institution: Princeton University

Date: 14:00 BST, 5th November 2025

Talk Title: Utilizing DNA to Measure Within-Race Skin Tone Disparities

Abstract: Today, scholars of racial inequality often strive to move beyond simply quantifying disparities across discrete racial categories (e.g., the Black-White achievement gap) to measuring social stratification as a function of continuous racialized characteristics, like skin tone. An overemphasis on discrete racial categories can serve to obscure meaningful within-race inequalities, whereas shifting the focus to various racialized characteristics highlights that there exists variation in how individuals with the same racial identity experience race and its consequences. However, interviewer-rated measures of skin tone contain a substantial amount of measurement error. In this study, we use penalized regression models to develop a genomic predictor of skin tone among non-Hispanic Black and Hispanic populations. We then utilize these novel genomic measures to study colorism in the contemporary United States. Preliminary results suggest that within-race socioeconomic gradients as a function of skin tone are far larger than previously estimated.

Bio: Sam Trejo is an Assistant Professor of Sociology at Princeton University. His research examines how social and biological factors interact to shape human development across the life course. He specializes in quantitative methods that combine quasi-experimental, computational, and biosocial approaches, often using large administrative and longitudinal datasets with genetic information.