# Evaluating DNA damage in a South American marsupial through exfoliated cells of the buccal mucosa

## TL;DR

This study uses a non-invasive DNA test on a marsupial species to assess genotoxic stress in fragmented forest habitats.

## Contribution

The study pioneers the use of the micronucleus test in a South American marsupial to evaluate DNA damage in fragmented environments.

## Key findings

- Karyolysis, pyknosis, and binucleated cells were more frequent at forest edges, indicating higher genotoxic stress.
- The micronucleus test proved effective as a non-invasive method for detecting DNA damage in wild marsupials.
- Marsupials in fragmented habitats showed increased susceptibility to genotoxic effects.

## Abstract

The edge effect alters microclimatic conditions and increases heavy metal pollution in monoculture landscapes, thereby exposing wildlife to toxic substances. This highlights the need for genotoxicity assessments in fragmented environments. The micronucleus test is a valuable biomarker for detecting DNA damage, though its use in wild mammals is recent. In this pioneering study, we applied the text to exfoliated buccal mucosa cells of Gracilinanus agilis, a South American marsupial, using the micronucleus test. Individuals were captured in a semideciduous forest in southern Goiás, central Brazil. We collected buccal cells from 41 individuals (13 females and 28 males) across 13 sampling sites. We identified six types of nuclear abnormalities: micronuclei, karyolysis, pyknosis, binucleated cells, karyorrhexis, and nuclear buds. Karyolysis, pyknosis, and binucleated cells were most frequent at the forest edge compared to the interior, indicating greater genotoxic stress in edge habitats. Our findings support the use of the micronucleus test as a non-invasive tool for monitoring DNA damage in wild populations and demonstrate that marsupials inhabiting forest edges are more susceptible to genotoxic effects.