Blotchy bass syndrome (BBS) is the presence of hyperpigmentation (melanosis) on the external surface of black basses. This condition has received increased attention from anglers and resource managers in recent years and is a popular topic of discussion and reporting on angling websites and blogging platforms.
Luke R Iwanowicz, Ph.D. (Former Employee)
Science and Products
Functional and Molecular Bioassay Core Technology Team
About the Research The Functional and Molecular Bioassay Core Technology Team (CTT) as part of the Environmental Health Program utilizes reporter assays, quantitative gene expression analyses, and high-throughput sequencing methods to produce functional endpoints across a broad scope of environmental topics and sample matrices.
Intersex in Male Smallmouth Bass in the Missisquoi River in Vermont: Understanding Factors that Can Lead to Endocrine Disruption in Field Settings
The presence of testicular oocytes (intersex) in male smallmouth bass ( Micropterus dolomieu) in the Missisquoi River in Vermont varied over the period of the study and was not related to concentrations of known endocrine disrupting chemicals in the River. Although previous studies have shown linkages between endocrine disrupting chemical exposures and intersex in fish, these results indicate that...
Human and Ecological Health Impacts Associated with Water Reuse and Conservation Practices
Human and Ecological Health Impacts Associated with Water Reuse and Conservation Practices
Endocrine Disrupting Chemicals and Prevalence of Intersex in Fish Populations in New Jersey
Endocrine disrupting chemicals (EDCs) are compounds with the potential to interfere with normal endocrine communication in organisms.
Molecular characterization of unknown virus isolated from the introduced species, the Northern snake head (Channa argus), present in the Chesapeake Bay Watershed
Molecular characterization of unknown virus isolated from the introduced species, the Northern snake head ( Channa argus), present in the Chesapeake Bay Watershed
Evaluating the pathogenicity and replication of a novel aquareovirus that infects the endangered fountain darter, Etheostoma fonticola
Evaluating the pathogenicity and replication of a novel aquareovirus that infects the endangered fountain darter, Etheostoma fonticola
Prevalence of novel, emerging hepatitis viruses in wild white suckers and their association with liver tumors in the Great Lakes region
Prevalence of novel, emerging hepatitis viruses in wild white suckers and their association with liver tumors in the Great Lakes region
Endocrine Disrupting Chemicals and Prevalence of Intersex in Fish Populations in New Jersey
NJ WSC and Leetown Science Center scientists in cooperation with the New Jersey Department of Environmental Protection were tasked with characterizing endocrine disruption in smallmouth bass from New Jersey.
Molecular tools and methodologies
Molecular tools and methodologies are used designed and used for diverse applications. These applications can be used to assess questions of threatened and endangered species, population and conservation biology, ecological communities, microbial diversity, molecular epidemiology and genomics of non-model organisms among many others. Successful integration of these tools and technologies greatly...
New Hepatitis B Virus Discovered in White Sucker (Catostomus commersonii)
The first known hepatitis B virus to infect fish (white sucker; Catostomus commersonii) has been discovered by U.S. Geological Survey (USGS) scientists.
Channel Catfish (Ictalurus punctatus) White Blood Cells are Functionally Modulated by Estrogens
Estrogens are recognized as modulators of immune responses in mammals, but how these effects might occur in fish was not understood. U.S. Geological Survey (USGS) scientists published findings that fish white blood cells (leukocytes) have specific estrogen receptors (ERs)—a discovery that moves scientists one step closer to understanding the connection between exposure to estrogenic substances and...
Biological Activity of Steroid Hormones in U.S. Streams
Testing of U.S. streams has detected glucocorticoid and androgen biological activity. In a collaborative study between the National Cancer Institute (NCI), Laboratory of Receptor Biology and Gene Expression, the U.S. Geological Survey (USGS), and others, scientists studied the potential for the biological activity in streams of glucocorticoids and androgens hormones—both potential endocrine...
2022 Blotchy Bass Syndrome Biosurveillance Project
Blotchy bass syndrome (BBS) is the presence of hyperpigmentation (melanosis) on the external surface of black basses. This condition has received increased attention from anglers and resource managers in recent years and is a popular topic of discussion and reporting on angling websites and blogging platforms.
Primary Filtration
Clay Raines performs primary filtration of pasteurized wastewater in the Biosafety Level-3 Lab
Clay Raines performs primary filtration of pasteurized wastewater in the Biosafety Level-3 Lab
Hepatitis B virus genome
Plaintext description:
Plaintext description:
Multimode, microplate reader used to measure optical density
Multimode, microplate reader
Primary hepatocytes isolated from experimental smallmouth bass
Screen capture of primary hepatocytes isolated from experimental smallmouth bass (Micropterus dolomieu) visualized following image-based flow cytometric analysis
Screen capture of primary hepatocytes isolated from experimental smallmouth bass (Micropterus dolomieu) visualized following image-based flow cytometric analysis
USGS scientist preparing plates for yeast bioassay screening
USGS scientists working at laboratory fume hood
USGS scientists working at laboratory fume hood
Image-based flow cytometer for cell population analysis
Image-based flow cytometer for cell population analysis
Image-based flow cytometer for cell population analysis
nCounter SPRINT† system simultaneously analyzes transcript abundance
The nCounter SPRINT† system simultaneously analyzes transcript abundance of hundreds of genes in a single sample
The nCounter SPRINT† system simultaneously analyzes transcript abundance of hundreds of genes in a single sample
Science and Products
Functional and Molecular Bioassay Core Technology Team
About the Research The Functional and Molecular Bioassay Core Technology Team (CTT) as part of the Environmental Health Program utilizes reporter assays, quantitative gene expression analyses, and high-throughput sequencing methods to produce functional endpoints across a broad scope of environmental topics and sample matrices.
Intersex in Male Smallmouth Bass in the Missisquoi River in Vermont: Understanding Factors that Can Lead to Endocrine Disruption in Field Settings
The presence of testicular oocytes (intersex) in male smallmouth bass ( Micropterus dolomieu) in the Missisquoi River in Vermont varied over the period of the study and was not related to concentrations of known endocrine disrupting chemicals in the River. Although previous studies have shown linkages between endocrine disrupting chemical exposures and intersex in fish, these results indicate that...
Human and Ecological Health Impacts Associated with Water Reuse and Conservation Practices
Human and Ecological Health Impacts Associated with Water Reuse and Conservation Practices
Endocrine Disrupting Chemicals and Prevalence of Intersex in Fish Populations in New Jersey
Endocrine disrupting chemicals (EDCs) are compounds with the potential to interfere with normal endocrine communication in organisms.
Molecular characterization of unknown virus isolated from the introduced species, the Northern snake head (Channa argus), present in the Chesapeake Bay Watershed
Molecular characterization of unknown virus isolated from the introduced species, the Northern snake head ( Channa argus), present in the Chesapeake Bay Watershed
Evaluating the pathogenicity and replication of a novel aquareovirus that infects the endangered fountain darter, Etheostoma fonticola
Evaluating the pathogenicity and replication of a novel aquareovirus that infects the endangered fountain darter, Etheostoma fonticola
Prevalence of novel, emerging hepatitis viruses in wild white suckers and their association with liver tumors in the Great Lakes region
Prevalence of novel, emerging hepatitis viruses in wild white suckers and their association with liver tumors in the Great Lakes region
Endocrine Disrupting Chemicals and Prevalence of Intersex in Fish Populations in New Jersey
NJ WSC and Leetown Science Center scientists in cooperation with the New Jersey Department of Environmental Protection were tasked with characterizing endocrine disruption in smallmouth bass from New Jersey.
Molecular tools and methodologies
Molecular tools and methodologies are used designed and used for diverse applications. These applications can be used to assess questions of threatened and endangered species, population and conservation biology, ecological communities, microbial diversity, molecular epidemiology and genomics of non-model organisms among many others. Successful integration of these tools and technologies greatly...
New Hepatitis B Virus Discovered in White Sucker (Catostomus commersonii)
The first known hepatitis B virus to infect fish (white sucker; Catostomus commersonii) has been discovered by U.S. Geological Survey (USGS) scientists.
Channel Catfish (Ictalurus punctatus) White Blood Cells are Functionally Modulated by Estrogens
Estrogens are recognized as modulators of immune responses in mammals, but how these effects might occur in fish was not understood. U.S. Geological Survey (USGS) scientists published findings that fish white blood cells (leukocytes) have specific estrogen receptors (ERs)—a discovery that moves scientists one step closer to understanding the connection between exposure to estrogenic substances and...
Biological Activity of Steroid Hormones in U.S. Streams
Testing of U.S. streams has detected glucocorticoid and androgen biological activity. In a collaborative study between the National Cancer Institute (NCI), Laboratory of Receptor Biology and Gene Expression, the U.S. Geological Survey (USGS), and others, scientists studied the potential for the biological activity in streams of glucocorticoids and androgens hormones—both potential endocrine...
2022 Blotchy Bass Syndrome Biosurveillance Project
Blotchy bass syndrome (BBS) is the presence of hyperpigmentation (melanosis) on the external surface of black basses. This condition has received increased attention from anglers and resource managers in recent years and is a popular topic of discussion and reporting on angling websites and blogging platforms.
Blotchy bass syndrome (BBS) is the presence of hyperpigmentation (melanosis) on the external surface of black basses. This condition has received increased attention from anglers and resource managers in recent years and is a popular topic of discussion and reporting on angling websites and blogging platforms.
Primary Filtration
Clay Raines performs primary filtration of pasteurized wastewater in the Biosafety Level-3 Lab
Clay Raines performs primary filtration of pasteurized wastewater in the Biosafety Level-3 Lab
Hepatitis B virus genome
Plaintext description:
Plaintext description:
Multimode, microplate reader used to measure optical density
Multimode, microplate reader
Primary hepatocytes isolated from experimental smallmouth bass
Screen capture of primary hepatocytes isolated from experimental smallmouth bass (Micropterus dolomieu) visualized following image-based flow cytometric analysis
Screen capture of primary hepatocytes isolated from experimental smallmouth bass (Micropterus dolomieu) visualized following image-based flow cytometric analysis
USGS scientist preparing plates for yeast bioassay screening
USGS scientists working at laboratory fume hood
USGS scientists working at laboratory fume hood
Image-based flow cytometer for cell population analysis
Image-based flow cytometer for cell population analysis
Image-based flow cytometer for cell population analysis
nCounter SPRINT† system simultaneously analyzes transcript abundance
The nCounter SPRINT† system simultaneously analyzes transcript abundance of hundreds of genes in a single sample
The nCounter SPRINT† system simultaneously analyzes transcript abundance of hundreds of genes in a single sample
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government