Acute GenX exposure induces spinal deformations and arrhythmia, and alters expression of genes involved in cardiac, vascular, neural, and visual systems during zebrafish (Danio rerio) early development

This study assessed the potential for GenX exposure to exert adverse effects during early development of zebrafish using morphological and physiological assessments, and further performed gene expression analysis on sublethal exposures to evaluate the underlying toxicogenomics. Zebrafish embryos exposed to GenX concentrations of 0.5 – 20000 mg/L were assessed at 24, 48, and 72 hours post-fertilization (hpf) for morphology, physiology, and survival. Shallow RNA-sequencing analysis of 9465 transcripts identified 38 genes that were consistently differentially expressed at 0.5, 1, 2, and 10 mg/L GenX exposures (compared to control at 72 hpf). Downregulated genes are associated with neurotransmission (6 genes) and visual response (10 genes), and upregulated genes are expressed in or regulate the cardiovascular system (7 genes). Our results suggest acute adverse effects by the alternative PFAS, GenX, in early zebrafish development by altering expression of genes involved in or regulating the heart and vascular tissue, neurotransmission, and visual response. Overall design: Examination of effects on GenX on zebrafish embryos.