Click here for more information about Dr. Sarah Tishkoff.

Abstract:

Africa is thought to be the ancestral homeland of all modern human populations.  It is also a region of tremendous cultural, linguistic, climatic, and genetic diversity.   Despite the important role that African populations have played in human history, they remain one of the most underrepresented groups in human genomics studies. A comprehensive knowledge of patterns of variation in African genomes is critical for a deeper understanding of human genomic diversity, the identification of functionally important genetic variation, the genetic basis of adaptation to diverse environments and diets, and for reconstructing modern human origins. African populations practice diverse subsistence patterns (hunter-gatherers, pastoralists, agriculturalists, and agro-pastoralists) and live in diverse environments with differing pathogen exposure (tropical forest, savannah, coastal, desert, low altitude, and high altitude) and, therefore, are likely to have experienced local adaptation. In this talk I will discuss results of analyses of genome-scale genetic variation in geographically, linguistically, and ethnically diverse African populations in order to reconstruct human evolutionary history in Africa, African and African American ancestry, as well as the genetic basis of adaption to diverse environments.

Dr. Francois Spitz | Spitz Lab

Bio:
PhD from Université Paris 6 (France)
Group Leader at the European Molecular Biology Laboratory (2006-2015) (Heidelberg, Germany)
Head of Research Unit at the Institut Pasteur (2015-2019) (Paris, France)
Professor, The University of Chicago (2019-.)

Abstract:
The mechanisms that regulate the efficiency and specificity of interactions between distant genes and cis-regulatory elements such as enhancers play a central role in shaping the specific regulatory programs that control cell fate and identity. In particular, the (epi)genetic elements that organize the 3D folding of the genome in specific loops and domains have emerged as key determinants of this process. I will discuss our current views on how 3D genome architecture is organized, how it influences gene regulatory interactions and illustrate how alterations of the mechanisms and elements that organize genomes in 3D could contribute to genomic disorders and genome evolution.

Dr. Maria Antonietta Tosches | Tosches Lab

Abstract:
The cerebral cortex is arguably the brain area that underwent the most profound transformations in vertebrate brain evolution. The expansion of the cerebral cortex in mammals was accompanied by an explosion of neuronal diversity. To discover general principles underlying the evolution of neuron types and circuits, we study the simple cerebral cortices of non-mammalian vertebrates. Our recent work has focused on the Spanish newt Pleurodeles waltl, a species with a key phylogenetic position in the vertebrate tree. We are investigating the neuroanatomy, cell type composition, and function of the Pleurodeles brain using a combination of modern neuroscience tools.

Our work on amphibians and reptiles indicates that the cerebral cortex of ancestral tetrapods was layered, with two main classes of neurons with distinct laminar positions, molecular identities, and long-range projections. In salamanders, these two layers are generated sequentially from multipotent progenitors in an outside-in sequence. We propose that in mammals new types of pyramidal neurons evolved from these two ancestral classes by diversification, through the emergence of novel gene regulatory interactions during neuronal differentiation.

Dr. Carrie Adler | Adler Lab

Bio:
Carrie is currently an Assistant Professor in the Department of Molecular Medicine at Cornell University, where she started her lab in 2015. She attended college at Wesleyan University and afterwards worked as a technician with Bruce Mayer at Harvard Medical School, studying signal transduction pathways. For graduate school, Carrie enrolled in the Tetrad program at UCSF, joining Cori Bargmann's lab to study neural development in C. elegans. As a postdoc, Carrie trained with Alejandro Sánchez Alvarado at the University of Utah and the Stowers Institute for Medical Research.

Abstract:
Throughout our lives, we are constantly exposed to insults, including injuries, disease, and environmental toxins. Frequently referred to as a ‘fountain of youth’ given their potential for rejuvenation, stem cells have the capacity to restore damaged tissue. In most model organisms, regenerative capacity is limited and stem cells are scarce, which has made it difficult to pinpoint the mechanisms regulating their behavior. In addition, stem cell exhaustion occurs as we age, diminishing our ability to repair damaged tissues. Finally, while we have made significant progress in recapitulating organ growth in vitro, how might these tissues be used in humans to restore physiological function?

My research program has probed these questions in an emerging model organism, planarian flatworms. These animals have long been regarded as champion regenerators because they can rapidly replace any tissue that’s been damaged or lost, including the nervous system. The basis of this unlimited renewal lies in an abundant population of stem cells. My lab’s primary goals are to understand how these cells sense and respond to injury, and how they maintain genome integrity through repeated cell divisions that occur during regeneration.

 Dr. Sarah Tishkoff | Tishkoff Lab

Sarah Tishkoff is the David and Lyn Silfen University Professor in Genetics and Biology at the University of Pennsylvania, holding appointments in the School of Medicine and the School of Arts and Sciences. She is also Director of the Penn Center for Global Genomics and Health Equity.

Dr. Tishkoff studies genomic and phenotypic variation in ethnically diverse Africans. Her research combines field work, laboratory research, and computational methods to examine African population history and how genetic variation can affect a wide range of traits – for example, why humans have different susceptibility to disease, how they metabolize drugs, and how they adapt through evolution.

Dr. Tishkoff is a member of the National Academy of Sciences and a recipient of an NIH Pioneer Award, a David and Lucile Packard Career Award, a Burroughs/Wellcome Fund Career Award, an ASHG Curt Stern award, and a Penn Integrates Knowledge (PIK) endowed chair. She is a member of the Scientific Advisory Panel for the Packard Fellowships for Science and Engineering and the Board of Global Health at the National Academy of Sciences and is on the editorial boards at PLOS Genetics, Genome Research; G3 (Genes, Genomes, and Genetics);Cell.

Her research is supported by grants from the National Institutes of Health, the National Science Foundation, the Chan Zuckerberg Institute, and the American Diabetes Association.

Abstract:
Africa is the ancestral homeland of all modern human populations within the past 300,000 years.  It is also a region of tremendous cultural, linguistic, climatic, phenotypic and genetic diversity.   Despite the important role that African populations have played in human history, they remain one of the most underrepresented groups in human genomics studies. A comprehensive knowledge of patterns of variation in African genomes is critical for a deeper understanding of human evolutionary history and the identification of functionally important genetic variation that plays a role in both normal variation and disease risk.  Here I will describe our studies of genomic variation in ethnically and geographically diverse Africans in order to reconstruct human evolutionary history and identify candidate genes that play a role in adaptation to infectious disease, diet, high altitude, stature, and skin color. I will highlight recent research integrating data from a genome wide association study of skin pigmentation in Africans and scans of natural selection from whole genome sequencing. Combining high-throughput reporter assays, Hi-C, CRISPR-based editing, and melanin content assays, we identified novel regulatory variants that impact melanin levels in vitro and modulate human skin color variation. Additionally, we identified a novel gene regulating pigmentation by impacting genes involved in oxidative phosphorylation and melanogenesis. These results provide insights into the mechanisms underlying human skin color diversity and adaptive evolution.