How can the Zebrafish Model be applied to current regulatory test paradigms?

Ioanna Katsiadaki
CEFAS Weymouth Laboratory, UK
Dr Katsiadaki described some basic mechanisms of chemically-induced epigenomic effects that could be detected using existing OECD test guidelines involving fish. She also emphasised the need for validation studies that link epigenetic markers and adverse outcome ― a critical step for regulation. Dr Katsiadaki said that adversity can be assigned within relatively few multigenerational studies as part of the validation process and that sampling at multiple time points and tissues is essential. The ultimate aim is to discover early predictive markers (FET). Future challenges include answering the following questions:
-    Where do we start in terms of fish line?
-    How do we confirm epigenetic nature-need functional assays?
-    Permanent vs. transient changes; heritable vs. non-heritable changes?
-    What are the fundamental differences between amniotic and non-amniotic species on epigenetic marking (role of female versus male in fish and mammals; sex determination mechanisms)?