Sarah Anne Tishkoff (born December 26, 1965) is an American geneticist and the David and Lyn Silfen Professor in the Department of Genetics and Biology at the University of Pennsylvania.
[5] Her more recent work includes the largest genomic study across ethnically diverse Africans, and the identification of novel genetic variants associated with skin color.
Her father was a professor of hematology and oncology at the University of California, Los Angeles and later the Director of the Red Cross for the Midwest of the United States.
This initial four-month-long trip, funded by the David and Lucile Packard Career Award, allowed her to pursue fieldwork that led to research in African population history and the genetics of variable traits and disease.
Tishkoff completed her formal education upon acquiring her PhD in genetics from Yale University in 1996, under the continued advisement of Kenneth Kidd.
While working in the Kidd Lab, Tishkoff developed an interest in African genomics and evolution, leading her to write her thesis on the “Patterns of nuclear haplotype frequency variation and linkage disequilibrium in a global sample of human populations”.
Shortly after completing her PhD, Tishkoff continued the research started in her thesis, and consequently published a paper titled “Global patterns of linkage disequilibrium at the CD4 locus and modern human origins” in the journal Science.
The central aims of her research are to better understand the origins of modern humans and the histories of African populations, and the genetic underpinnings of disease susceptibility.
One of the key findings in this area of research includes the discovery of genetic signatures of interbreeding between anatomically modern humans and extinct hominins.
[17] Sarah Tishkoff and colleagues also focus their research on acquiring genomic and phenotypic data from geographically and culturally distinct African populations, which are underrepresented in genetic studies[18] and whose analysis may uncover new aspects of human evolutionary history, including susceptibility to diseases and migration patterns.
[20] Additionally, based on this research they have claimed that migrations from non-African populations into northern Africa resulted in increased genetic diversity in that region.
[21] Another focus of Tishkoff’s research group is understanding how different geographical and environmental influences correlate with genotypic and phenotypic changes in African populations.
[4] Haplotype analysis of Med and A- allele mutations at the G6PD locus revealed that their increased frequency occurred after the agricultural practices began.
[4] Tishkoff and colleagues suggested that agriculture led to greater exposure to malaria, which created a selective pressure for alleles that confer resistance.
[22] This research suggested that there is a strong association between these allele frequencies and the presence of malaria, and that its analysis would help to find factors that affect malarial susceptibility and resistance.
[24] These mutations are an example of convergent evolution due to the shared cultural selective pressures of animal domestication and milk consumption, and they are a clear case of gene-culture coevolution.
[25] In 2012, Tishkoff participated in a study published in Genome Biology that compared the hemoglobin levels between populations living at high and low altitudes in Ethiopia.
The study was based on a sample of 57 African populations consisting of 611 individuals and a comparative set of 132 non-Africans from the Middle East, Asia, and the Americas.
Researchers measured participants' PTC bitter taste sensitivity using a modified version of the Harris - Kalmus threshold method, sequenced genomes, and completed haplotype and genotype–phenotype association analyses.
[29] Tishkoff has numerous open-access online videos of topics relevant to her work, released in conjunction with a variety of research organizations, academic conferences, and educational foundations.
She participated in the Howard Hughes Medical Institute's Biointeractive Lecture Series on Bones, Stones, and Genes: The Origin of Modern Humans.
[30] Similarly, Tishkoff has released a short series of research talks on African Genomics with the organization iBiology, whose mission is to "convey, in the form of open-access free videos, the excitement of modern biology and the process by which scientific discoveries are made".
[2] At her time at University of Pennsylvania, Tishkoff became an Integrates Knowledge Professor in 2008 for her work in African ancestry, lactase persistence, and taste sensitivity.