High-throughput in vivo genotoxicity testing: an automated readout system for the somatic mutation and recombination test (SMART)

PLoS One. 2015 Apr 1;10(4):e0121287. doi: 10.1371/journal.pone.0121287. eCollection 2015.

Abstract

Genotoxicity testing is an important component of toxicity assessment. As illustrated by the European registration, evaluation, authorization, and restriction of chemicals (REACH) directive, it concerns all the chemicals used in industry. The commonly used in vivo mammalian tests appear to be ill adapted to tackle the large compound sets involved, due to throughput, cost, and ethical issues. The somatic mutation and recombination test (SMART) represents a more scalable alternative, since it uses Drosophila, which develops faster and requires less infrastructure. Despite these advantages, the manual scoring of the hairs on Drosophila wings required for the SMART limits its usage. To overcome this limitation, we have developed an automated SMART readout. It consists of automated imaging, followed by an image analysis pipeline that measures individual wing genotoxicity scores. Finally, we have developed a wing score-based dose-dependency approach that can provide genotoxicity profiles. We have validated our method using 6 compounds, obtaining profiles almost identical to those obtained from manual measures, even for low-genotoxicity compounds such as urethane. The automated SMART, with its faster and more reliable readout, fulfills the need for a high-throughput in vivo test. The flexible imaging strategy we describe and the analysis tools we provide should facilitate the optimization and dissemination of our methods.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Drosophila / genetics*
  • Drosophila / physiology
  • Hair / metabolism
  • Image Processing, Computer-Assisted
  • Mutagenicity Tests / methods*
  • Mutation
  • Recombination, Genetic*
  • Wings, Animal / metabolism

Associated data

  • figshare/10.6084/m9.figshare.1299073

Grants and funding

This work was supported by National Research Foundation of Korea (NRF) grants funded by the Korean government (MSIP) (No. 2007-00559, 2009-0090095 and 2014R1A2A1A10050531), Gyeonggi-do, and KISTI. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.