The convergence of synthetic biology and artificial intelligence is widening the gap between technological advancement and existing regulatory frameworks — a phenomenon known as regulatory lag. As global competition intensifies to capture a synthetic biology market projected to reach approximately $70 billion by 2030, nations are responding to this challenge through markedly different approaches. This study applies a comparative legal methodology, drawing on co-evolutionary theory and the Law 1.0/2.0/3.0 framework, to analyze the regulatory responses of the United States, United Kingdom, Japan, and South Korea. The analysis reveals that national differences stem less from institutional design choices than from the triggers that initiate regulatory change, yielding four distinct co-evolutionary pathways. In the United States, a shift in the judicial environment prompted regulatory adaptation; in the United Kingdom, a political transition created the conditions for legislative reform; and in Japan, administrative reinterpretation of existing rules enabled regulatory adjustment. South Korea represents a fundamentally different case. By enacting the world’s first standalone synthetic biology legislation prior to full technological maturation, Korea has pursued a top-down co-evolutionary model in which institutional design precedes and shapes the trajectory of technological development. Three conclusions emerge from this analysis: there is no single optimal co-evolutionary pathway; institutional flexibility determines the sustainability of co-evolution; and co-evolution can itself be an object of proactive design. For Korea's preemptive model to prove effective, it requires a sufficient scientific foundation, institutional flexibility, and coherence with existing regulatory frameworks — conditions that offer a reference point for other nations confronting similar governance challenges.