Assessing CometChip technology for DNA damage studies in non-model species: distinct UV-induced responses in turtles and mammals.

Objective: We evaluated the feasibility of using the high-throughput CometChip to assess DNA damage in non-model species. Specifically, we measured UVA-induced damage in fibroblasts from five turtle and four mammalian species with diverse life histories and cancer rates.

Results: Turtles exhibited significantly higher endogenous DNA damage than mammals but showed lower UVA-induced damage after both 2-min and 5-min exposures. At 5 min, bats exhibited the most DNA damage (21.3%), followed by mice (11.3%). Elephants showed intermediate responses (Asian: 6.49%, African: 3.58%), while all turtles remained below 3%, suggesting resilience to oxidative stress. Despite the assay's ability to detect DNA damage across species, several challenges emerged. Endogenous damage varied widely both within and between species. Differences in culture requirements between turtles and mammals limited experimental standardization. Additionally, characterizing species-specific responses is challenging, as multiple cell lines per species are often unavailable for non-model organisms, making it difficult to account for intraspecific variation. Addressing these limitations will be crucial for conducting robust comparative studies of DNA damage responses in future research.