Julie Horvath, Ph.D.
Director, Genomics & Microbiology Research Laboratory
B.S. (Zoology with a concentration in Genetics) Michigan State University, 1996
Ph.D. (Human Genetics) Case Western Reserve University, 2004
Research Associate Professor, Department of Biology, North Carolina Central University, Durham, NC
Dr. Julie Horvath is a comparative evolutionary genomicist interested in understanding the evolutionary forces that have shaped primate genomes and that cause human disease. Genetic and genomic comparisons between humans and our closest relatives, the primates, are crucial for understanding our own evolution and unique characteristics. The foundation of Dr. Horvath’s research is based on species relationships, or phylogenies, which she first established for lemurs, and more recently, for all primates. These species relationships are applied to many of her research questions. Several examples of Horvath’s research investigate the connection between genotype (DNA sequence) and phenotype (traits and characteristics) that make flora and fauna unique.
Dr. Horvath received a B.S. in Zoology with a concentration in Genetics from Michigan State University in 1996 and a Ph.D. in Genetics in 2004 from Case Western Reserve University in Cleveland, Ohio. In 2008, Dr. Horvath became a founding member of the Duke University Primate Genomics Initiative, a joint partnership between the Department of Evolutionary Anthropology at Duke University and the Institute for Genome Sciences & Policy. The goal of the Primate Genomics Initiative is to facilitate collaborative evolutionary genomics research projects between researchers using nonhuman and human primate models across diverse fields by combining research, training and service. Dr. Horvath is now the Director of the Genomics & Microbiology Research Laboratory in the Nature Research Center, North Carolina Museum of Natural Sciences, and is jointly appointed as Research Associate Professor in the Biology Department at North Carolina Central University where she teaches courses and advises graduate students. Dr. Horvath remains involved with the Duke University Primate Genomics Initiative where she is an adjunct member of the Evolutionary Anthropology Department and affiliated with the Institute for Genome Sciences & Policy.
Horvath’s comparative genomic foundation provides an exciting way to integrate research from multiple disciplines since genomic analyses can be applied to many different research questions. Relative to other primates, lemur genomic resources are very limited and part of Horvath’s research program involves creating resources to address exciting biological questions. For example, the gray mouse lemur is one of only a few primates known to undergo torpor, a process similar to hibernation. While in torpor, the mouse lemurs regulate body temperature and resource intake. Understanding this metabolic regulation will offer clues into human conditions such as obesity and diabetes, which result from problems in metabolic regulation. The gray mouse lemur is currently the only lemur with any genome sequence (2X coverage), but there is no gene annotation information known. Horvath is currently using a variety of next-generation sequencing methods to obtain and annotate mouse lemur genes in the partial mouse lemur genome in an effort to understand some of the genes and pathways involved in mouse lemur torpor and, by extension, human conditions. In the future Horvath will use these tools to dissect important pathways involved in these processes.
A collaborative project with Michael Platt, Lauren Brent and Pate Skene at Duke University as well as Laurie Santos at Yale and members of the Caribbean Primate Research Center is incorporating genetic and genomic techniques with behavioral and neuroscientific methods to elucidate genotype-phenotype associations in rhesus macaques. This work was originally funded through an NIH stimulus grant and is now continued with 5-year NIH research grant. This collaborative project is identifying macaque genotypes that are associated with social behavior heterogeneity and have similarities to human autism spectrum disorders. The population of rhesus macaques lives on the small island of Cayo Santiago, off the coast of Puerto Rico, and offers many future opportunities to combine field-based research with genomic methods to study macaque behavior and ecology. An exciting collaborative project between Dr. Horvath and Greg Wray’s group, Christine Wall’s group, Courtney Babbitt and Olivier Fedrigo at Duke University, which is funded by an NSF HOMINID grant, is integrating anthropological theories with genomics to understand the evolution of recent primate dietary shifts by focusing on humans and chimpanzees. Positive selection assays focusing on regulatory regions identified several genes involved in tooth development that have significant sequence changes between humans and chimpanzees relative to macaques. Differences in relative enamel thickness are evident throughout primates and other mammals and offer an opportunity to explore some of the key genes associated with this dietary trait. Through this collaboration Horvath became interested in understanding the evolution of several genes involved in dental enamel thickness and the associated diseases, amelogenesis imperfectas (AI), since relative enamel thickness is important for proper tooth function and dental health. Horvath’s group is investigating the evolution and positive selection of several genes involved in enamel thickness and maturation in the broader primate and mammalian context to offer clues into the evolution of genes and regulatory regions associated with dental diseases.
In a recently initiated collaboration, Dr. Horvath, Dr. Urban (the Genomics & Microbiology Research Laboratory Assistant Director) and Rob Dunn’s group at NC State are beginning an armpit biodiversity project to identify the microbes that live under primate armpits. This entails a sample swab under the armpits that will be genetically analyzed by sequencing small regions of the genomes of the microbes that live there. This will start out as an exploratory project to identify armpit microbes that will rely on citizen scientists to collect some of the human data. Since animal “fragrance” is partially determined by what is under the armpit, this has implications for mate choice and has exciting evolutionary implications. Therefore, this will soon expand to sampling multiple other primates and mammals. Citizen scientists can help us explore some of the factors affecting microbe biodiversity, which may be dictated by the deodorant used, geographic location and the type of soap and water used for bathing.