Supply chains operate in a multifaceted institutional landscape which exerts pressure on managers to reconcile the institutional pressures with their business imperatives. This paper introduces a novel conceptual framework grounded in neo-institutional theory to understand the adaptive sustainability behavior of supply chains through the concepts of institutional crossover and mutation. Resting on the concept of genetic evolution, the paper suggests the notion of institutional chromosomes to denote institutional elements that evolve through interaction with other institutions or due to internal transformations. Institutional crossover occurs when two or more institutions interact, resulting in modifications to existing regulative, normative, and cognitive elements. Conversely, institutional mutation manifests the internal changes or stimulus forces such as cultural transformation or leadership shift that influence the institutional elements. Using examples from sustainable supply chain practices, the paper illustrates these changes and their impacts on firms’ compliance, resilience, and competitiveness.