Margaret Lynn Pearson Adam, M.D.
Assistant Professor

My research interest and areas of clinical specialization include dysmorphology, hemihyperplasia and overgrowth, syndromes, limb anomalies, and human teratology.
I am a practicing geneticist with the pediatric/adult genetics clinic in the Division of Medical Genetics, Department of Human Genetics.

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Lora J.H. Bean, Ph.D.
Assistant Professor
Director, Molecular Laboratory

Working with Dr. Stephanie Sherman (Human Genetics) and Dr. Ken Dooley (Pediatrics), we are ascertaining a large sample of Down syndrome with complete atrioventricular septal defect (AVSD) from the Sibley Heart Center, Children's Healthcare of Atlanta and the surrounding Southeastern region. A biological sample, family history, and an environmental exposure history are collected from each family. Combined with the Down syndrome population previously ascertained by the Sherman Lab, this Down syndrome with AVSD population will allow us to conduct several lines of investigation into the genetics causes of AVSD and analyze our results in the context of environmental exposures. In addition, we are interested in the role that genetic variation within known congenital heart defect genes may play in the etiology of heart defects in Down syndrome.

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R. Dwain Blackston, M.D.
Associate Professor

My research interests and areas of clinical specialization include dysmorphology, Down syndrome, fetal alcohol syndrome, and developmental disabilities.
I am a practicing geneticist with the pediatric/adult genetics clinic for the Division of Medical Genetics, Department of Human Genetics. I also lead the genetic clinic's outreach program, which services rural regions of Georgia.

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Mark Bouzyk, Ph.D.
Assistant Professor
Director, Center for Medical Genomics

The Center for Medical Genomics (CMG) has a key role in serving as a Center of Excellence for experimental studies in genetic variation by linking human genetics to health and disease. In order to achieve this mission the CMG has established state of the art technologies in genetic sample management, high throughput DNA extraction and genetic analysis capabilities in DNA sequencing, mutation detection and genotyping supported by an advanced laboratory management information system and data architecture. This infrastructure provides for the opportunity to conduct linkage analysis, candidate gene and genomic association studies to identify susceptibility genes for both common and rare diseases particularly in the areas of Oncology, Neurological and Psychiatric disorders. There is also the opportunity to facilitate the increasing demand for pharmacogenetics. In addition, to help meet the increasing need for translational medicine solutions and by working closely with other laboratories within the Emory community the CMG is ideally placed to explore ways to provide faster, more cost efficient and streamlined genetic tests using rapidly advancing genetic technologies.

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Center for Medical Genomics

Tamara Caspary, Ph.D.
Assistant Professor

Even though we now have the sequence of the mouse genome, we still do not know what most of the genes do. The Caspary Lab is interested in identifying novel genes that are important for mouse embryogenesis, specifically in the nervous system. In order to do this in an unbiased way, we use phenotype driven screens in the mouse. We include random point mutations with the chemical mutagen, N-ethylnitrosourea (ENU). Through a three generation breeding scheme we identify recessive mutations of interest by looking for those which cause morphological defects midway through embryogenesis. Now that we have the complete sequence of the mouse genome it is straightforward to clone the genes responsible for the phenotypes we find. In the course of our screens we have identified seven mutations that change cell fate in the nervous system.

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Caspary Laboratory

Anthony W.S. Chan, Ph.D.
Assistant Professor

The research interest of our laboratory includes: 1. The development of a trangenic non-human primate model for genetic diseases such as Huntington's and Alzheimer's etc., 2. The biology of the differentiation control of embryonic stem cells, 3. The development of cell replacement therapy, and 4. The biological aspects of human infertility.
My lab aims to develop a non-human primate model with modified genetic background, similar to that of the patient, to understand the disease and the development of efficacious medication. Specifically, we are developing a non-invasive system using the latest transgenic and imaging (PET and MRI) technologies that would allow us to monitor the expression pattern of disease-related genes and the progression of the disease. This imaging technique will also be used for monitoring of cell fate following transplantation in cell replacement study. Due to the close genetic background and physiological resemblance with humans, we believe that being able to monitor disease development in non-human primates will provide invaluable information for accurate justification of novel medications, therapeutic procedures and the understanding of the diseases.

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Chan Laboratory

Bradford W. Coffee, Ph.D., F.A.C.M.G.
Assistant Professor
Director, Molecular Laboratory

My research is focused on understanding the role that epigenetics has in human disease and translating what is learned in the basic research laboratory to clinical practice.  The primary focus of my work is the development of a high-throughput population screen for fragile X syndrome and sex chromosome aneuploidies based on quantitative assessment of DNA methylation of the FMR1 gene.  I will use this assay to screen a large cohort of consecutive newborns to accurately determine the incidence of fragile X syndrome in the general population, as well as in specific ethnic and racial groups.  In addition, I have an interest in diseases caused by alterations in chromatin structure leading to changes in gene expression.  These alterations in chromatin structure are often associated with changes in DNA methylation patterns.  To that end, I have developed an assay to test for DNA methylation changes at 11p15, which are associated with both Beckwith-Wiedemann and Silver-Russell syndromes.  I am also interested in novel methods to discover imprinted regions in the genome.  The discovery of these regions will lead to the development of clinical tests that can detect alterations in chromatin structure and gene expression that cause human disease.

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Karlene Coleman, R.N., M.N., C.G.C.
Senior Associate

My background is in nursing and genetic counseling. I currently serve as a genetic counselor for Children's Healthcare of Atlanta (CHOA) at Egleston. My research interests include several collaborative projects involving CHOA, Emory, and the Centers for Disease Control and Prevention including incidence, morbidity and mortality after cardiac surgery, and clinical presentations in 22q11 deletions. This syndrome is one of the more common chromosome problems seen in the pediatric population and is currently estimated to occur in 1 of every 4000 live births.

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Karen N. Conneely, Ph.D.
Assistant Professor

My research focuses on statistical issues affecting genetic association studies. Ongoing methodological work addresses 1) the impact of genotype quality on the validity of different types of association studies, 2) methods to adjust for the many correlated tests performed in contemporary association studies, which may involve dense SNPs, overlapping haplotypes, and/or related phenotypes, 3) extension of these methods to meta-analyses, and 4) detection of copy number variants in genome-wide array data. Current applied work includes projects on the genetics of post-traumatic stress disorder, breast cancer, essential tremor and Parkinson’s disease, and longevity.

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Joseph F. Cubells, M.D., Ph.D.
Associate Professor

My research primarily focuses on the molecular genetic regulation of plasma dopamine beta-hydroxylase activity to test putative functional variants, identified in population-based studies, at the molecular level. In the Cubells Lab we are also studying other biochemical traits associated with psychiatric illness, such as neurochemical markers of hypothalamic-pituitary-adrenal (HPA) axis function. We investigate these phenotypes using candidate gene approaches. Fundamental to this task is to characterize linkage disequilibrium and haplotype structure at loci of interest.
An additional interest of mine is understanding and treating psychiatric symptoms with the 22q11 deletion syndrome. Toward this end, I am collaborating with a multi-disciplinary group to develop the Emory-CHOA 22q11 DS Research Clinic.

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Cubells Laboratory

David J. Cutler, Ph.D.
Assistant Professor

I am a theoretical population geneticist by training and inclination, and the work my lab does is most easily thought of as population genetics applications to human disease studies. In particular my lab devotes most of its time and energy to building tools to analysis whole genome data sets in an attempt to discover alleles associated with disease. Most of our work lies in the intersection of human genomics / population genetics / biostatistics and computer science. Loosely put, we take human genomics data, think about that data like a population geneticist, develop relatively straightforward biostatistical tests for that data, and then implement those tests using somewhat sophisticated computer science approaches. The motto of our lab might be “Everything is easier with a 1000 CPU computer cluster!”

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Dean J. Danner, Ph.D.

In Memoriam

Michael P. Epstein, Ph.D.
Assistant Professor

Our research focuses on the development and application of statistical methods to identify genetic variants that influence complex diseases and disease-related quantitative traits. Our current methodological work centers on powerful multi-locus approaches for association mapping in candidate-gene or genome-wide studies of complex traits. We are also interested in developing methods for detecting and conducting inference on copy-number variation that are found throughout the genome. Applied projects currently focus on the genetics of schizophrenia, PTSD, autism, and epilepsy.

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Andrew Escayg, Ph.D.
Assistant Professor

The Escayg Lab uses a combination of human and mouse genetics, mouse disease models and genome analysis/bioinformatics in order to determine the molecular basis of inherited neurological disorders. We have a broad interest in neurological disease and the disorders that we are currently working on include epilepsy, ataxia and other movement disorders, and migraine. The long-term goal of our research is to develop better diagnositc tools and more effective therapeutic agents.
Of particular interest is the role of voltage-gated ion channels in disease. Voltage-gated ion channels play a critical role in neuronal signaling and the maintenance of normal nervous system function.

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Escayg Laboratory

W. Andrew Faucett, M.S., C.G.C.
Instructor

In 2000 I accepted a fellowship position at the Centers for Disease Control and Prevention (CDC) to learn the public health system and provide assistance with CDC genetic efforts. While at the CDC some of the projects I have been involved with include the development and distribution of educational tools targeting primary healthcare providers (Genetics in Clinical Practice: A Team Approach); development of a genetic laboratory specialty in CLIA; and collaborative efforts to improve rare disease testing.

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Paul M. Fernhoff, M.D., F.A.A.P, F.A.C.M.G.
Associate Professor

Each year over 4 million newborns in the U.S. are screened for an increasing number of genetic disorders. I am the principal investigator (P.I.) in a 3 year study, funded by the CDC, to establish a pediatric office based program to screen healthy male infants for Duchenne Muscular Dystrophy (DMD). Because most males with DMD are not diagnosed until after 3 years of age, the purpose of our study is to diagnose males before they develop symptoms, and to provide them and their families early intervention services and genetic counseling.
I am also the P.I. on studies, funded by Genzyme, to examine the effectiveness of enzyme replacement therapy for children and adults affected with lysosomal storage disorders (LSDs). The LSDs are a group of over 40 genetic disorders that cause progressive deterioration of multiple body systems. This therapy has been quite sucessful in several of the LSDs.

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Judith Fridovich-Keil, Ph.D.
Professor

Roles of galactose and galactose metabolism in normal development, homeostasis, and disease. Galactose and its derivatives serve as essential components of glycoproteins and glycolipids in humans and other species. As a component of milk, galactose also serves as a key energy source for mammals, especially infants. Impaired metabolism of galactose leads to the potentially lethal disease classic galactosemia. We are applying a combination of basic and clinical approaches using patients, mammalian cells, flies, and microbial systems to explore the underlying bases of pathophysiology in galactosemia, and to define the roles of galactose and galactose metabolism in normal development and homeostasis. We are further working to develop novel and improved forms of intervention for patients with galactosemia.

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Fridovich-Keil Laboratory

Kathryn Garber, Ph.D.
Instructor

One of the things I love about human genetics is that the data we get from research often outpaces our understanding, so it seems that there will always be mysteries to discover.  This wonder and excitement is what I try to convey to my students. I am involved in genetics education at Emory on several levels.  One of my main goals has been to ensure proper incorporation of human genetics into the new curriculum of Emory School of Medicine.  As part of this goal, I chaired the committee that developed the new Genetics and Evolution module for the first year medical curriculum and serve as course director for the class.  I also serve as the course director for Medical Genetics, which is a required class for our post-graduate clinical fellows.  Along with Andy Faucett, I am designing and teaching a human genetics course for physician assistant students.  Teaching students with many different backgrounds and future goals is an exciting challenge, and I enjoy the opportunity to think about human genetics from many different angles.

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Madhuri R. Hegde, Ph.D.
Assistant Professor
Director, Molecular Laboratory

The focus of the laboratory is to develop and perform comprehensive mutation analysis and interpretation for complex or challenging genetic disorders using multiple approaches. The primary focus of my clinical work is the development of a high-throughput sequencing assays for rare disorders using robotics, automated sequence platforms, oligonucleotide array platforms, robotics and using predictive analysis tools and biological testing.   My research is focused on functional analysis of sequence variants in inherited colon cancers and Muscular Dystrophies and translating what is learned in the basic research laboratory to clinical practice.  The ultimate goal is to create an algorithm that will be clinically useful for interpretation of novel sequence variants. Additionally, I have an interest in identifying novel genes in these diseases.  An understanding of the important changes will eventually provide an opportunity to improve the early detection of disease, and to target more effective treatment. 

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Peng Jin, Ph.D.
Assistant Professor

In the Jin Lab our research interest and goal is to understand the roles of non-coding RNAs in neural development and the pathogenesis of brain disorders. Currently, we are focusing on three areas: 1) the role of microRNA pathways in learning and memory; 2) the molecular basis of RNA-mediated neurodegeneration; and 3) the role of small non-coding RNAs in epigenetic regulation. The importance of non-coding RNAs has been increasingly recognized within the last several years, particularly with the identification of new classes of small RNAs, such as microRNAs (miRNAs). These non-coding RNAs play important roles in neural development and can be involved in neuronal translation control (miRNAs), transcription regulation (small modulatory RNAs in the fate specification of adult neural stem cells), and can be pathogenic leading to human diseases as well (non-coding repeats in neurodegeneration).

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Jin Laboratory

David H. Ledbetter, Ph.D.
Robert W. Woodruff Professor of Human Genetics
Director, Division of Medical Genetics

The Ledbetter Lab focuses on the molecular characterization of human development disorders. Specifically, we are interested in the mechanisms and consequences of chromosomal abnormalities (gene dosage imbalance and genomic imprinting) that result in abnormal brain development, mental retardation and behavioral disorders such as autism.

We previously pioneered the use of FISH technology for the detection of human microdeletion disorders, and developed the first genome-wide assay to detect telomere imbalances in ~5% of children with unexplained mental retardation. The rapid development of microarray technology for whole-genome analysis of copy number is revolutionizing cytogenetics in research and clinical diagnostic laboratories. We have developed a “molecular karyotype” on an oligonucleotide array platform which allows detection of deletions or duplications >500 kb in size anywhere in the genome, and >50 kb in selected critical regions (compared to 5 Mb resolution of chromosome banding). This technology is leading to the discovery of new microdeletion syndromes and can be systematically used to develop a Gene Dosage Map for the human genome.

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Ledbetter Laboratory

Shi-Hua Li, M.D.
Associate Professor

My research interests focus on trinucleotide expansion and neurodegenerative diseases.
Nine inherited neurodegenerative disorders are caused by an expansion of a polyglutamine tract in the associated disease proteins. Of these diseases, Huntington Disease (HD) has been well studied and shows altered gene expression that contributes to the disease process. We found that mutant huntingtin, which contains an expanded polyglutamine tract in its N-terminal region, binds to the transcription factor, Sp1, and affects Sp1-mediated gene expression.
Our research is currently focusing on how mutant polyglutamine proteins abnormally bind to transcription factors to affect gene expression and whether the altered gene expression is associated with disease progression.

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Xiao-Jiang Li, M.D., Ph.D.
Distinguished Professor of Human Genetics

To address these important issues, we will use a variety of approaches, including genetic manipulation of animal models, molecular and cell biological analysis of protein transport, and biochemical study of protein-protein interactions, to investigate the relationship between gene mutation and disease phenotypes. Specifically, we are currently investigating the effects of mutant proteins on the function of neurons and glia in the brain, gene transcription, and intracellular trafficking. The goal of our studies is to provide mechanistic insight into the pathogenesis of neurodegeneration caused by polyQ expansion and to help develop effective therapeutic strategies.

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Li Laboratory

Kenneth M. Loud, M.S., C.G.C.
Senior Associate
Co-Director, Genetic Counseling Program
Co-Director, Cancer Genetic Services

My research interests and areas of clinical specialization include cancer risk assessment and genetic counseling, strategies for improving access to cancer genetic services, genetic and environmental causes of cancer susceptibility, integration of clinical genetic services into public and private health care programs, and genetic counseling for preconceptional, perinatal and postnatal indications.

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Christa Lese Martin, Ph.D., F.A.C.M.G.
Associate Professor

One of the main goals of the Martin Lab is to identify and characterize cryptic telomere and other genomic rearrangements in patients with unexplained mental retardation and autism. We are interested in 1) determining the frequency of rearrangements in these populations, 2) studying the mechanism of abnormal chromosome formation, and 3) correlating genotype changes with phenotypic consequences. The delineation of genotype/phenotype correlations is important for clinical diagnosis and prognosis, and will help in determining which regions of the genome are tolerant to dosage imbalance versus those that are pathogenic. We have developed a "molecular ruler" strategy, which consists of clones equally spaced from the telomere of each chromosome up to 5 Mb, which we use to delineate the sizes of telomere rearrangements.
Another interest of our laboratory is the development of new technologies, such as array analysis, for more efficient identification of genome-wide imbalances.

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Martin Laboratory

Junmin Peng, Ph.D.
Assistant Professor

Recently, efforts in genomics have made many genome sequences available. The next step is research in proteomics. Mass spectrometry is a powerful technology for identifying proteins and their modifications such as phosphorylation and ubiquitination. Using a technique termed multidimensional liquid chromatography coupled tandem mass spectrometry, we can determine the identity of hundreds to thousands of protein components in a complex sample at a sensitivity in the femtomole range. We are also developing bioinformatics tools for proteomic analysis. Our interests are to map and profile proteins and their modifications in patients and animal models of neurodegenerative disease. Combining with tools in molecular and cell biology and genetics, we will explore the function of these proteins and their modifications in the development of these devastating disorders.

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Peng Laboratory

Michael R. Rossi, Ph.D.
Assistant Professor
Director, Clinical Cytogenetics and Molecular Genetics Laboratories

My research primarily focuses on the genetics of cancer predisposition and disease progression. I am interested in developing integrated molecular diagnostic tools to recognize patients who are at high risk for developing cancer and to identify novel somatic events that direct treatment strategies. To achieve this end, my laboratory seeks to redefine the karyotype in molecular terms. Using high-throughput array and sequencing technologies, we are working to combine multiple independent gene and whole genome querying methods into comprehensive disease specific analyses for clinical diagnostics.

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Katie Rudd, Ph.D., F.A.C.M.G
Assistant Professor

The Rudd lab studies chromosome breakage mechanisms, focusing on breaks at the ends of chromosomes.  Subtelomeres are the terminal regions of chromosomes just proximal of telomere repeats.  Rearrangements at the ends of chromosomes can cause mental retardation or exist as normal copy number variants.  Subtelomeres are a unique part of the genome, subject to elevated frequencies of breaks in mitosis and meiosis.  In order to understand the mechanism of subtelomeric breaks, we are fine-mapping breakpoints using high-resolution array CGH.  We predict that certain subtelomeric sequences are predisposed to break and are subsequently repaired by non-homologous end-joining.  

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Rudd Laboratory

Stephanie Sherman, Ph.D.
Professor

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Sherman Laboratory

Rani H. Singh, Ph.D.
Associate Professor
Director, Nutrition Program

Nutritional care is an essential component for the management of genetic disorders. Developing a comprehensive clinical nutrition program both for inpatients and outpatients with inborn errors of metabolism that can serve as a national model of clinical care has been a high priority in my career. My research interests focus on optimizing nutritional treatment of genetic disorders and developing patient education and community outreach stratregies through the Emory Genetics Metabolic Nutrition Program. The goals of these clinical research efforts are to develop nutritional treatment recommendations that promote optimal growth and development, and prevent adverse neurological and health consequences in individuals with metabolic disorders. Current research aimed at advancing treatment strategies include 1) interventions designed to effectively transition nutrition management from childhood to adulthood and 2) investigations of the relationship of individual genotypes and nutrition interventions as they relate to treatment outcomes. Other critical avenues to assure optimal nutritional care include recent programmatic efforts to bridge nutritional care with expanded Newborn Screening and genetics services provided through national programs.

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Yilang Tang, MD, PHD
Instructor

Trained as a psychiatrist in China and obtained my master degree in psychopharmacology and Ph. D degree in psychiatric genetics, my research has been focused on the molecular genetics of psychiatric disorders and psychopharmacology. Working closely with Dr. Cubells, I have been involved in several major projects, including the genetics of cocaine-induced psychosis and the biochemical genetics of dopamine beta-hydroxylase and Catechol-O-methyl-transferase. I am also working on the genetic analysis of cigarette smoking, dopamine–related gene studies of Alzheimer’s disease, epidemiology of autistic spectrum disorders in China.

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Catherine Tesla, M.S., C.G.C.
Instructor

My clinical background includes teratology, perinatal and cancer genetics. I am dually responsible for development, implementation and maintenance of clinical genetics education for patients and healthcare professionals, which includes writing, editing, and designing the monthly "Take the Genetic Challenge!" newsletter and the "Ask the Geneticist" website. Derived from my background in graphic design and art, I also develop and implement marketing strategies for our genetic laboratories and patient services, as well as lead the department website design and development team.

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James W. Thomas, Ph.D.
Assistant Professor

The Thomas Lab uses genomic technologies and resources to gain novel insights into the functional information encoded within the human genome. There is abundant phenotypic variation between species and within the human population. However, the genetic basis for most of this phenotypic variation is not known. The goal of our research is to use comparative genomics to address this fundamental gap in knowledge. In particular, our research uses a comparative genomics approach to identify when and how candidate functional genetic differences between species arose, and then to apply that knowledge to the development of better animal models of human disease and to a more complete understanding of the evolutionary history of the human genome. Ongoing projects in our laboratory include: the evaluation of a potential new mouse model of Lesch-Nyhan disease, targeted comparative mapping and sequencing in nonhuman primates, genomic characterization of a chromosome polymorphism in an avian model of social behavior, and analysis of near-identical but widely conserved segmental duplications on the X chromosome.

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Thomas Laboratory

Jeannie Visootsak, M.D., F.A.A.P
Assistant Professor

I am a Developmental-Behavioral Pediatrician and Medical Director of the Down Syndrome and Fragile X Syndrome clinics. My area of expertise is in neurodevelopmental disorders, particularly children with genetic syndromes.

My research interests and clinical specialization include management of individuals with Down Syndrome, Fragile X Syndrome, sex chromosomal aneuploidies, and X-linked mental retardation conditions.

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Stephen T. Warren, Ph.D.
William Patterson Timmie Professor of Human Genetics
Chairman, Department of Human Genetics
Professor of Pediatrics
Professor of Biochemistry

The Warren Lab research is directed toward understanding the mechanisms of inherited human diseases. A large component of the research program involves Fragile-X syndrome, a common cause of mental retardation and autism that is due to a trinucleotide repeat expansion in the FMR1 gene. The research is multifaceted and broad in approach. Biochemical approaches and model systems (mouse, fly and cell culture) are being used to study the mechanism of repeat expansion, associate gene methylation, their consequence on gene transcription and the function of the encoded protein. A variety of biochemical methods are used to understand the function of the FMR1 protein (FMRP), a selective RNA-binding protein that associates with the ribosome following nucleocytoplasmic shuttling. Recently we have linked Fragile-X syndrome to the microRNA pathway and begun a substantial new effort in the lab to understand this relationship as well as the role, generally, of microRNAs in human disease.

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Warren Laboratory

David Weinshenker, Ph.D.
Assistant Professor

My research program has active projects that pertain to drug addiction, epilepsy, depression, and neurodegenerative disease. We are particularly interested in how the loss of norepinephrine might contribute to neurological diseases. Norepinephrine is one of the most abundant neurotransmitters of the central and peripheral nervous systems, and regulates diverse biological functions. We use genetically engineered mice with altered norepinephrine systems to understand how norepinephrine influences physiology and behavior. Some examples are dopamine beta-hydroxylase knockout mice that are unable to synthesize norepinephrine signaling, norepinephrine transporter knockout mice that are unable to clear norepinephrine from the synapse and thus have excessive norephinephrine signaling, and various knockouts of individual adrenergic receptors.

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Weinshenker Laboratory

Michael Zwick, Ph.D.
Assistant Professor

The Zwick laboratory research aims to implement an experimental framework that can rapidly identify and characterize genomic variation. Genetic variation detection has often proven to be difficult, expensive and slow. The promise of genomics lies in the ability to conduct experiments that characterize genome-wide patterns of variation. These studies have typically been carried out in large industrial genome sequencing centers that reduce costs through economies of scale. Next-generation genomics technologies offer the promise of a genome sequencing center on every laboratory bench, producing vast quantities of genomic variation data at an ever-reduced cost. We are interested in harnessing next-generation DNA sequencing/resequencing technologies in order to make genomic variation detection rapid and inexpensive. Our ultimate goal is to understand how genome variation we observe contributes to variation in important phenotypes in humans, model organisms (like Drosophila) and microbial systems.