Grantee Research Project Results
The Effects of Endocrine Disrupting Compounds on Gulf Pipefish
EPA Grant Number: FP917497Title: The Effects of Endocrine Disrupting Compounds on Gulf Pipefish
Investigators: Rose, Emily
Institution: Texas A & M University
EPA Project Officer: Packard, Benjamin H
Project Period: August 27, 2012 through August 26, 2015
Project Amount: $126,000
RFA: STAR Graduate Fellowships (2012) RFA Text | Recipients Lists
Research Category: Fellowship - Biology , Academic Fellowships
Objective:
The main goals of this research are to: (1) determine the effect of endocrine disruptors on pipefish recruitment by testing how synthetic estrogen (EE2) exposure affects brood viability, juvenile sex determination and/or early development in gulf pipefish; and (2) understand the impacts EDCs have on natural populations of gulf pipefish in the Gulf of Mexico region using population genetics, gene expression biomarkers and evolutionary genomics.
Approach:
The first aim of the proposed research will be conducted in the laboratory to determine the effects of EDCs on pipefish recruitment. This study will determine the effects of EDCs on the parental pipefish by pairing non-exposed males with exposed females and non-exposed females with exposed males. Data will be collected on offspring viability using egg size, embryonic survivorship and size of juveniles at birth, as well as sex determination and early development of juveniles to determine the effects of exposure to EDCs. The second aim will ascertain whether or not EDCs are affecting natural populations of pipefish using field populations from across the Gulf of Mexico region, including Texas, Alabama and Florida. In addition, the second aim will investigate the impacts of endocrine disruptors on morphological and reproductive traits as well as quantify gene expression levels using real-time quantitative-PCR, focusing on candidate genes in exposed populations. Lastly, the second aim also will focus on the genetic structure of these populations using restriction-site associated DNA (RAD) markers and next-generation sequencing.
Expected Results:
Pipefish exposed to endocrine disruptors, such as EE2, are expected to have lower reproductive success, resulting in a decrease in recruitment in exposed populations. Egg viability also is expected to be lowest in the paired mating of an exposed male and female, compared to non-exposed individuals. Exposed juvenile pipefish are expected to show signs of feminization in male fish in addition to possible skewed sex ratios in exposed populations. Pipefish are expected to respond physiologically to endocrine disruptor contamination, resulting in changes in expression patterns across several genes. As a result of this study, several molecular markers will be developed as indicators of endocrine disruptor contamination. There also is the possibility of endocrine disruptor contamination causing changes in the genetic structure of exposed pipefish populations, as well as the pipefish’s genome, which will be detected using next-generation sequencing data.
Potential to Further Environmental/Human Health Protection
The proposed research represents a key step toward understanding the long-term effects of EDCs on the reproductive health of coastal fish populations in the Gulf of Mexico region. As a result of this study, molecular markers will be developed to assess impacts of pollutants and use population genomics to survey population structure over time to determine how long-term exposure to these contaminants affects natural populations. A better understanding of these impacts will provide the information necessary to achieve future goals, such as developing solutions to environmental contamination, and ultimately improve the water quality and well-being of the aquatic life within these ecosystems.
Supplemental Keywords:
endocrine disrupting compounds, synthetic estrogen (EE2), population geneticsProgress and Final Reports:
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.