With advances in biotechnology come potential changes in how college students may understand the nature of identity. This study explores sensemaking around the biological underpinnings of proclaimed "social" identities (e.g., race, class, and gender). Based on interviews with 34 undergraduate students recruited from two large public research universities in the United States, a conceptual model is offered to outline the general process of how students make sense of biological and/or social explanations of identity, including the role of controllability and essentialism. We discuss implications for multicultural education and teaching the "social construction" of identity in changing contexts.