Abstract
Current genotoxicity testing strategies face several challenges,
including a high incidence of misleading positive results that lead to
unnecessary animal testing, limited mechanistic insights, insufficient
integration of innovative methodologies, and a lack of quantitative
assessment. Despite rapid advancements in technology and scientific
understanding, genotoxicity testing batteries have remained largely
unchanged for years. To modernize genotoxicity assessment and
incorporate innovative approaches, the development of Integrated
Approaches for Testing and Assessment (IATAs) is essential. These
frameworks combine existing knowledge with data from New Approach
Methodologies (NAMs) aiming to reduce or eliminate reliance on in vivo
testing. Genotoxicity is particularly well-suited for IATA development
as numerous cutting-edge, non-animal methods have emerged in recent
years, including 3D test systems, Prediscreen®, MultiFlow®, ToxTracker®,
and transcriptomic-based biomarkers such as GENOMARK and TGx-DDI.
However, the integration of NAMs into IATAs must be systematic and
scientifically robust. In this process, the Adverse Outcome Pathway
(AOP) framework plays a crucial role by linking molecular-level events
to adverse health effects, thereby supporting the structured selection
of NAMs. This article explores the key challenges and gaps within the
current European regulatory frameworks for chemical compound
genotoxicity assessment and discuss how an AOP-based IATA can address
these issues. Additionally, we present a global AOP network for
permanent DNA damage, designed to guide IATA development and improve
regulatory decision-making. This integrated approach has the potential
to enhance the accuracy, efficiency, and ethical standards of
genotoxicity assessment while reducing reliance on animal testing.