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Full-Text Articles in Life Sciences

Origins Of An Unmarked Georgia Cemetery Using Ancient Dna Analysis, Andrew T. Ozga, Raul Y. Tito, Brian M. Kemp, Hugh Matternes, Alexandra J. Obregon-Tito, Leslie Neal, Cecil M. Lewis Jr. Aug 2019

Origins Of An Unmarked Georgia Cemetery Using Ancient Dna Analysis, Andrew T. Ozga, Raul Y. Tito, Brian M. Kemp, Hugh Matternes, Alexandra J. Obregon-Tito, Leslie Neal, Cecil M. Lewis Jr.

Andrew Ozga

Determining the origins of those buried within undocumented cemeteries is of incredible importance to historical archaeologists and, in many cases, the nearby communities. In the case of Avondale Burial Place, a cemetery in Bibb County, Georgia, in use from 1820 to 1950, all written documentation of those interred within it has been lost. Osteological and archaeological evidence alone could not describe, with confidence, the ancestral origins of the 101 individuals buried there. In the present study, we used ancient DNA extraction methods in well-preserved skeletal fragments from 20 individuals buried in Avondale Burial Place to investigate the origins of the …


Hierarchical Modeling And Differential Expression Analysis For Rna-Seq Experiments With Inbred And Hybrid Genotypes, Andrew Lithio, Dan Nettleton Jul 2019

Hierarchical Modeling And Differential Expression Analysis For Rna-Seq Experiments With Inbred And Hybrid Genotypes, Andrew Lithio, Dan Nettleton

Dan Nettleton

The performance of inbred and hybrid genotypes is of interest in plant breeding and genetics. High-throughput sequencing of RNA (RNA-seq) has proven to be a useful tool in the study of the molecular genetic responses of inbreds and hybrids to environmental stresses. Commonly used experimental designs and sequencing methods lead to complex data structures that require careful attention in data analysis. We demonstrate an analysis of RNA-seq data from a split-plot design involving drought stress applied to two inbred genotypes and two hybrids formed by crosses between the inbreds. Our generalized linear modeling strategy incorporates random effects for whole-plot experimental …


Saccharomyces Genome Database & Uniprot Bioinformatics Analysis, Ray A. Enke Dec 2018

Saccharomyces Genome Database & Uniprot Bioinformatics Analysis, Ray A. Enke

Ray Enke Ph.D.

This in class activity introduces basic bioinformatics analysis using the Saccharomyces Genome Database (SGD) and the UniProt Database. The yeast URA3 gene is studied in this activity, however, any other yeast gene can be substituted. This activity is designed for novice instructors and students for implementation into core biology lecture or lab courses.


Crispr-Cas9 Nuclear Dynamics And Target Recognition In Living Cells, Hanhui Ma, Li-Chun Tu, Ardalan Naseri, Maximiliaan Huisman, Shaojie Zhang, David Grünwald, Thoru Pederson May 2017

Crispr-Cas9 Nuclear Dynamics And Target Recognition In Living Cells, Hanhui Ma, Li-Chun Tu, Ardalan Naseri, Maximiliaan Huisman, Shaojie Zhang, David Grünwald, Thoru Pederson

David Grünwald

The bacterial CRISPR-Cas9 system has been repurposed for genome engineering, transcription modulation, and chromosome imaging in eukaryotic cells. However, the nuclear dynamics of clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 (Cas9) guide RNAs and target interrogation are not well defined in living cells. Here, we deployed a dual-color CRISPR system to directly measure the stability of both Cas9 and guide RNA. We found that Cas9 is essential for guide RNA stability and that the nuclear Cas9-guide RNA complex levels limit the targeting efficiency. Fluorescence recovery after photobleaching measurements revealed that single mismatches in the guide RNA seed sequence …


Open Consent, Biobanking And Data Protection Law: Can Open Consent Be ‘Informed’ Under The Forthcoming Data Protection Regulation?, Dara Hallinan, Michael Friedewald Jan 2015

Open Consent, Biobanking And Data Protection Law: Can Open Consent Be ‘Informed’ Under The Forthcoming Data Protection Regulation?, Dara Hallinan, Michael Friedewald

Michael Friedewald

This article focuses on whether a certain form of consent used by biobanks – open consent – is compatible with the Proposed Data Protection Regulation. In an open consent procedure, the biobank requests consent once from the data subject for all future research uses of genetic material and data. However, as biobanks process personal data, they must comply with data protection law. Data protection law is currently undergoing reform. The Proposed Data Protection Regulation is the culmination of this reform and, if voted into law, will constitute a new legal framework for biobanking. The Regulation puts strict conditions on consent …


Cloning And Expression Analysis Of Drosophila Extracellular Cu Zn Superoxide Dismutase, Michael J. Blackney, Rebecca Cox, David Shepherd, Joel D. Parker Dec 2014

Cloning And Expression Analysis Of Drosophila Extracellular Cu Zn Superoxide Dismutase, Michael J. Blackney, Rebecca Cox, David Shepherd, Joel D. Parker

Joel D Parker

In the present study, we cloned and sequenced the mRNAs of the Sod3 [extracellular Cu Zn SOD (superoxide dismutase)] gene in Drosophila and identified two mRNA products formed by alternative splicing. These products code for a long and short protein derived from the four transcripts found in global expression studies (Flybase numbers Dmel\CG9027, FBgn0033631). Both mRNA process variants contain an extracellular signalling sequence, a region of high homology to the Sod1 (cytoplasmic Cu Zn SOD) including a conserved AUG start, with the longer form also containing a hydrophobic tail. The two fully processed transcripts are homologous to Caenorhabditis elegans Sod3 …


The Empire Of Cancer: Gene Patents And Cancer Voices, Matthew Rimmer Dec 2013

The Empire Of Cancer: Gene Patents And Cancer Voices, Matthew Rimmer

Matthew Rimmer

In his book, The Emperor of All Maladies, Siddhartha Mukherjee writes a history of cancer — ‘It is a chronicle of an ancient disease — once a clandestine, “whispered-about” illness — that has metamorphosed into a lethal shape-shifting entity imbued with such penetrating metaphorical, medical, scientific, and political potency that cancer is often described as the defining plague of our generation’.Increasingly, an important theme in the history of cancer is the role of law, particularly in the field of intellectual property law. It is striking that a number of contemporary policy debates over intellectual property and public health have concerned …


Encyclopedia Of Animal Behavior, A. Payne, P. Starks, Aviva Liebert Jun 2013

Encyclopedia Of Animal Behavior, A. Payne, P. Starks, Aviva Liebert

Aviva E Liebert

The Encyclopedia of Animal Behavior has engaged-with great success-the efforts of many of the best behavioral biologists of the 21st century. Section editors drawn from the most accomplished behavioral scientists of their generation have enrolled an international cast of highly respected thinkers and writers-all of whom have taken great care and joy in illuminating every imaginable corner of animal behavior. This comprehensive work covers not only the usual topics such as communication, learning, sexual selection, navigation, and the history of the field, but also emerging topics in cognition, animal welfare, conservation, and applications of animal behavior. The large section on …


Direct Dna Binding Activity Of The Fanconi Anemia D2 Protein, Woo-Hyun Park, Steven Margossian, Andrew Horwitz, Amanda Simons, Alan D'Andrea, Jeffrey Parvin Feb 2013

Direct Dna Binding Activity Of The Fanconi Anemia D2 Protein, Woo-Hyun Park, Steven Margossian, Andrew Horwitz, Amanda Simons, Alan D'Andrea, Jeffrey Parvin

Amanda Simons

It is known that the Fanconi anemia D2 protein is vital for protecting the genome from DNA damage, but what activities this protein has are unknown. In these experiments we purified full-length Fanconi anemia protein D2 (FANCD2), and we found that FANCD2 bound to DNA with specificity for certain structures: double strand DNA ends and Holliday junctions. Proteins containing patient-derived mutations or artificial variants of the FANCD2 protein were similarly expressed and purified, and each variant bound to the Holliday junction DNA with similar affinity as did the wild-type protein. There was no single discrete domain of FANCD2 protein that …


Fanconi Anemia Protein Fancd2 Inhibits Trf1 Polyadp-Ribosylation Through Tankyrase1-Dependent Manner, Alex Lyakhovich, Maria Ramirez, Andres Castella, Amanda Simons, Jeffrey Parvin, Jordi Suralles Dec 2012

Fanconi Anemia Protein Fancd2 Inhibits Trf1 Polyadp-Ribosylation Through Tankyrase1-Dependent Manner, Alex Lyakhovich, Maria Ramirez, Andres Castella, Amanda Simons, Jeffrey Parvin, Jordi Suralles

Amanda Simons

Background: Fanconi anemia (FA) is a rare autosomal recessive syndrome characterized by developmental abnormalities, progressive bone marrow failure, and predisposition to cancer. The key FA protein FANCD2 crosstalks with members of DNA damage and repair pathways that also play a role at telomeres. Therefore, we investigated whether FANCD2 has a similar involvement at telomeres. Results: We reveal that FANCD2 may perform a novel function separate to the FANCD2/BRCA pathway. This function includes FANCD2 interaction with one of the telomere components, the PARP family member tankyrase-1. Moreover, FANCD2 inhibits tankyrase-1 activity in vitro. In turn, FANCD2 deficiency increases the polyADPribosylation of …


Identification Of Genetic Risk Associated With Prostate Cancer Using Ancestry Informative Markers, Bradford Wilson Nov 2012

Identification Of Genetic Risk Associated With Prostate Cancer Using Ancestry Informative Markers, Bradford Wilson

Bradford Wilson

A total of 77 ancestry informative markers (AIMs) within surrounding candidate gene regions were genotyped and haplotyped using Pyrosequencing in 358 unrelated men enrolled in a PCa genetic association study at the Howard University Hospital between 2000 and 2004. Sequence analysis of promoter region single-nucleotide polymorphisms (SNPs) to evaluate disruption of transcription factor-binding sites was conducted using in silico methods.

Results: Eight AIMs were significantly associated with PCa risk after adjusting for age and West African ancestry. SNP rs1993973 (intervening sequences) had the strongest association with PCa using the log-additive genetic model (P=0.002). SNPs rs1561131 (genotypic, P=0.007), rs1963562 (dominant, P=0.01) …


Regulatory Elements Of Xenopus Col2a1 Drive Cartilaginous Gene Expression In Transgenic Frogs, Ryan R. Kerney, Brian K. Hall, James Hanken Oct 2012

Regulatory Elements Of Xenopus Col2a1 Drive Cartilaginous Gene Expression In Transgenic Frogs, Ryan R. Kerney, Brian K. Hall, James Hanken

Ryan Kerney

This study characterizes regulatory elements of collagen 2α1 (col2a1) in Xenopus that enable transgene expression in cartilage-forming chondrocytes. The reporters described in this study drive strong cartilage-specific gene expression, which will be a valuable tool for further investigations of Xenopus skeletal development. While endogenous col2a1 mRNA is expressed in many embryonic tissues, its expression becomes restricted to tadpole and adult chondrocytes. This chondrocyte-specific expression is recapitulated by col2a1 reporter constructs, which were tested through I-SceI meganuclease-mediated transgenesis. These constructs contain a portion of the Xenopus tropicalis col2a1 intron, which aligns to a cartilage-specific intronic enhancer that has been well characterized …


Disparities In Allele Frequencies And Population Differentiation For 101 Disease-Associated Single Nucleotide Polymorphisms Between Puerto Ricans And Non-Hispanic Whites, Josiemer Mattei, Laurence D. Parnell, Chao-Qiang Lai, Bibiana Garcia-Bailo, Xian Adiconis, Jian Shen, Donna Arnett, Serkalem Demissie, Katherine L. Tucker, Jose M. Ordovas Aug 2012

Disparities In Allele Frequencies And Population Differentiation For 101 Disease-Associated Single Nucleotide Polymorphisms Between Puerto Ricans And Non-Hispanic Whites, Josiemer Mattei, Laurence D. Parnell, Chao-Qiang Lai, Bibiana Garcia-Bailo, Xian Adiconis, Jian Shen, Donna Arnett, Serkalem Demissie, Katherine L. Tucker, Jose M. Ordovas

Katherine L. Tucker

Background: Variations in gene allele frequencies can contribute to differences in the prevalence of some common complex diseases among populations. Natural selection modulates the balance in allele frequencies across populations. Population differentiation (FST) can evidence environmental selection pressures. Such genetic information is limited in Puerto Ricans, the second largest Hispanic ethnic group in the US, and a group with high prevalence of chronic disease. We determined allele frequencies and population differentiation for 101 single nucleotide polymorphisms (SNPs) in 30 genes involved in major metabolic and disease-relevant pathways in Puerto Ricans (n = 969, ages 45–75 years) and compared them to …


Natural Disease Resistance In Threatened Staghorn Corals, Steven V. Vollmer, David I. Kline Dec 2011

Natural Disease Resistance In Threatened Staghorn Corals, Steven V. Vollmer, David I. Kline

Steve Vollmer

Disease epidemics have caused extensive damage to tropical coral reefs and to the reef-building corals themselves, yet nothing is known about the abilities of the coral host to resist disease infection. Understanding the potential for natural disease resistance in corals is critically important, especially in the Caribbean where the two ecologically dominant shallow-water corals, Acropora cervicornis and A. palmata, have suffered an unprecedented mass die-off due to White Band Disease (WBD), and are now listed as threatened under the US Threatened Species Act and as critically endangered under the IUCN Red List criteria. Here we examine the potential for natural …


Genetic Diversity And Connectivity In The Threatened Staghorn Coral (Acropora Cervicornis) In Florida, Elizabeth M. Hemond, Steven V. Vollmer Dec 2011

Genetic Diversity And Connectivity In The Threatened Staghorn Coral (Acropora Cervicornis) In Florida, Elizabeth M. Hemond, Steven V. Vollmer

Steve Vollmer

Over the past three decades, populations of the dominant shallow water Caribbean corals, Acropora cervicornis and A. palmata, have been devastated by white-band disease (WBD), resulting in the listing of both species as threatened under the U.S. Endangered Species Act. A key to conserving these threatened corals is understanding how their populations are genetically interconnected throughout the greater Caribbean. Genetic research has demonstrated that gene flow is regionally restricted across the Caribbean in both species. Yet, despite being an important site of coral reef research, little genetic data has been available for the Florida Acropora, especially for the staghorn coral, …


When Should Judges Admit Or Compel Genetic Tests?, Diane Hoffmann, Karen Rothenberg Oct 2011

When Should Judges Admit Or Compel Genetic Tests?, Diane Hoffmann, Karen Rothenberg

Diane Hoffmann

No abstract provided.


Clustering With Exclusion Zones: Genomic Applications, Mark Segal, Yuanyuan Xiao, Fred Huffer Dec 2010

Clustering With Exclusion Zones: Genomic Applications, Mark Segal, Yuanyuan Xiao, Fred Huffer

Mark R Segal

Methods for formally evaluating the clustering of events in space or time, notably the scan statistic, have been richly developed and widely applied. In order to utilize the scan statistic and related approaches, it is necessary to know the extent of the spatial or temporal domains wherein the events arise. Implicit in their usage is that these domains have no “holes”—hereafter “exclusion zones”—regions in which events a priori cannot occur. However, in many contexts, this requirement is not met. When the exclusion zones are known, it is straightforward to correct the scan statistic for their occurrence by simply adjusting the …


Consent To The Use Of Stored Dna For Genetics Research: A Survey Of Attitudes In The Jewish Population, Marc D. Schwartz, Karen H. Rothenberg, Linda Joseph, Judith Benkendorf, Caryn Lerman Dec 2009

Consent To The Use Of Stored Dna For Genetics Research: A Survey Of Attitudes In The Jewish Population, Marc D. Schwartz, Karen H. Rothenberg, Linda Joseph, Judith Benkendorf, Caryn Lerman

Karen H. Rothenberg

No abstract provided.


Judging Genes: Implications Of The Second Generation Of Genetic Tests In The Courtroom, Diane E. Hoffmann, Karen H. Rothenberg Dec 2009

Judging Genes: Implications Of The Second Generation Of Genetic Tests In The Courtroom, Diane E. Hoffmann, Karen H. Rothenberg

Karen H. Rothenberg

The use of DNA tests for identification has revolutionized court proceedings in criminal and paternity cases. Now, requests by litigants to admit or compel a second generation of genetic tests – tests to confirm or predict genetic diseases and conditions – threaten to affect judicial decision-making in many more contexts. Unlike DNA tests for identification, these second generation tests may provide highly personal health and behavioral information about individuals and their relatives and will pose new challenges for trial court judges. This article reports on an original empirical study of how judges analyze these requests and uses the study results …


Social Implications Of Genetic Testing, Karen H. Rothenberg Dec 2009

Social Implications Of Genetic Testing, Karen H. Rothenberg

Karen H. Rothenberg

This paper examines the social implications of predictive genetic testing and its impact on the insurance industry. Although the Human Genome Project has the potential to improve the health of our nation, it also may serve as a means of highlighting genetic differences among individuals and ethnic groups. Thus, if we are to reach the full promise of the Project, society must address the public's fears of genetic discrimination in insurance and employment context. Following an analysis of state and federal legislation on genetic privacy and discrimination, the paper concludes with a challenge to the insurance industry to work with …


Genetic Information And The Workplace: Legislative Approaches And Policy Challenges, Karen H. Rothenberg, Barbara Fuller, Mark Rothstein, Troy Duster, Mary Jo Ellis Kahn, Rita Cunningham, Beth Fine, Kathy Hudson, Mary-Claire King, Patricia Murphy, Gary Swergold, Francis Collins Dec 2009

Genetic Information And The Workplace: Legislative Approaches And Policy Challenges, Karen H. Rothenberg, Barbara Fuller, Mark Rothstein, Troy Duster, Mary Jo Ellis Kahn, Rita Cunningham, Beth Fine, Kathy Hudson, Mary-Claire King, Patricia Murphy, Gary Swergold, Francis Collins

Karen H. Rothenberg

No abstract provided.


The Scarlet Gene: Behavioral Genetics, Criminal Law, And Racial And Ethnic Stigma, Karen H. Rothenberg, Alice Wang Dec 2009

The Scarlet Gene: Behavioral Genetics, Criminal Law, And Racial And Ethnic Stigma, Karen H. Rothenberg, Alice Wang

Karen H. Rothenberg

Imagine that a scientist from the state university asks you and your family to participate in a study on a particular gene variant associated with alcoholism. The project focuses on your ethnic group, the Tracy Islanders, who have a higher incidence of alcoholism, as well as a higher incidence of the gene variant, than the general population. You will not be informed whether you have the gene variant, but your participation in the study might help scientists develop drugs to help individuals control their addiction to alcohol. You have a family history of alcoholism, and you are concerned that your …


When Should Judges Admit Or Compel Genetic Tests?, Diane E. Hoffmann, Karen H. Rothenberg Dec 2009

When Should Judges Admit Or Compel Genetic Tests?, Diane E. Hoffmann, Karen H. Rothenberg

Karen H. Rothenberg

No abstract provided.


Cancer Genetic Susceptibility Testing: Ethical And Policy Implications For Future Research And Clinical Practice, Benjamin S. Wilfond, Karen H. Rothenberg, Elizabeth J. Thomson, Caryn Lerman Dec 2009

Cancer Genetic Susceptibility Testing: Ethical And Policy Implications For Future Research And Clinical Practice, Benjamin S. Wilfond, Karen H. Rothenberg, Elizabeth J. Thomson, Caryn Lerman

Karen H. Rothenberg

No abstract provided.


Toward A Framework Of Mutualism: The Jewish Community In Genetics Research, Karen H. Rothenberg, Amy B. Rutkin Dec 2009

Toward A Framework Of Mutualism: The Jewish Community In Genetics Research, Karen H. Rothenberg, Amy B. Rutkin

Karen H. Rothenberg

No abstract provided.


The Unblazed Trail: Bioinformatics And The Protection Of Genetic Knowledge, Lawrence M. Sung Sep 2009

The Unblazed Trail: Bioinformatics And The Protection Of Genetic Knowledge, Lawrence M. Sung

Lawrence M. Sung

No abstract provided.


Short Telomeres In Short-Lived Males: What Are The Molecular And Evolutionary Causes?, Stephanie Jemielity, Masayuki Kimura, Karen M. Parker, Joel D. Parker, Xiaojian Cao, Abraham Aviv, Laurent Keller Apr 2007

Short Telomeres In Short-Lived Males: What Are The Molecular And Evolutionary Causes?, Stephanie Jemielity, Masayuki Kimura, Karen M. Parker, Joel D. Parker, Xiaojian Cao, Abraham Aviv, Laurent Keller

Joel D Parker

Telomere length regulation is an important aspect of cell maintenance in eukaryotes, since shortened telomeres can lead to a number of defects, including impaired cell division. Although telomere length is correlated with lifespan in some bird species, its possible role in aging and lifespan determination is still poorly understood. Here we investigate telomere dynamics (changes in telomere length and attrition rate) and telomerase activity in the ant Lasius niger, a species in which different groups of individuals have evolved extraordinarily different lifespans. We found that somatic tissues of the short-lived males had dramatically shorter telomeres than those of the much …


Silencing Of Retrotransposons In Dictyostelium By Dna Methylation And Rnai., Markus Kuhlmann, Branimira E. Borisova, Markus Kaller, Pontus Larsson, Dirk Stach, Jianbo Na, Ludwig Eichinger, Frank Lyko, Victor R. Ambros, Fredrik Soderbom, Christian Hammann, Wolfgang Nellen Nov 2005

Silencing Of Retrotransposons In Dictyostelium By Dna Methylation And Rnai., Markus Kuhlmann, Branimira E. Borisova, Markus Kaller, Pontus Larsson, Dirk Stach, Jianbo Na, Ludwig Eichinger, Frank Lyko, Victor R. Ambros, Fredrik Soderbom, Christian Hammann, Wolfgang Nellen

Victor R. Ambros

We have identified a DNA methyltransferase of the Dnmt2 family in Dictyostelium that was denominated DnmA. Expression of the dnmA gene is downregulated during the developmental cycle. Overall DNA methylation in Dictyostelium is approximately 0.2% of the cytosine residues, which indicates its restriction to a limited set of genomic loci. Bisulfite sequencing of specific sites revealed that DnmA is responsible for methylation of mostly asymmetric C-residues in the retrotransposons DIRS-1 and Skipper. Disruption of the gene resulted in a loss of methylation and in increased transcription and mobilization of Skipper. Skipper transcription was also upregulated in strains that had genes …


Decreased Expression Of Cu–Zn Superoxide Dismutase 1 In Ants With Extreme Lifespan, Joel D. Parker, Karen M. Parker, Barbara H. Sohal, Rajindar S. Sohal, Laurent Keller Mar 2004

Decreased Expression Of Cu–Zn Superoxide Dismutase 1 In Ants With Extreme Lifespan, Joel D. Parker, Karen M. Parker, Barbara H. Sohal, Rajindar S. Sohal, Laurent Keller

Joel D Parker

Reactive oxygen species, the by-products of oxidative energy metabolism, are considered a main proximate cause of aging. Accordingly, overexpression of the enzyme Cu–Zn superoxide dismutase 1 (SOD1) can lengthen lifespan of Drosophila melanogaster in the laboratory. However, the role of SOD1 as a main determinant of lifespan has been challenged on the grounds that overexpression might be effective only in compromised genetic backgrounds. Moreover, interspecific comparisons show lower levels of antioxidant activities in longer-lived species, suggesting that life-span extension may evolve through less reactive oxygen species generation from the mitochondria rather than higher expression of SOD1. The tremendous variation in …


Intracellular Coexpression Of Epidermal Growth Factor Receptor, Her-2/Neu, And P21ras In Human Breast Cancers: Evidence For The Existence Of Distinctive Patterns Of Genetic Evolution That Are Common To Tumors From Different Patients, Stanley E. Shackney, Agnese A. Pollice, Charles A. Smith, Laura E. Janocko, Lillian Sweeney, Kathryn A. Brown, Sarita G. Singh, Lingping Gu, Robert Yakulis, Joseph F. Lucke Jan 1998

Intracellular Coexpression Of Epidermal Growth Factor Receptor, Her-2/Neu, And P21ras In Human Breast Cancers: Evidence For The Existence Of Distinctive Patterns Of Genetic Evolution That Are Common To Tumors From Different Patients, Stanley E. Shackney, Agnese A. Pollice, Charles A. Smith, Laura E. Janocko, Lillian Sweeney, Kathryn A. Brown, Sarita G. Singh, Lingping Gu, Robert Yakulis, Joseph F. Lucke

Joseph Lucke

Multiparameter flow cytometry studies were performed on cells from the primary tumors of 94 patients with breast cancer. Correlated cellular measurements of cell DNA content, Her-2/neu, epidermal growth factor receptor (EGFR), and p21ras levels were performed on each of 5,000 to 100,000 cells from each tumor. When criteria for positivity were matched with those in common use for immunohistochemical studies, 28 of 94 (30\%) breast cancers were classified as positive for Her-2/neu overexpression. When similar criteria were applied to the EGFR measurements, 23 of 94 (24\%) cases were classified as positive for EGFR overexpression. Similarly, 23 of 94 (24\%) cases …