Trainee Author: Bárbara Domingues Bitarello, PhD
Postdoctoral Researcher, Department of Genetics
Perelman School of Medicine, University of Pennsylvania
(Photo courtesy Bitarello)
In this month’s Trainee Paper Spotlight, Bitarello et al. define a simple yet powerful new statistic for detecting long-term balancing selection, called Non-Central Deviation or NCD. After demonstrating NCD has high power, via simulation, application of NCD to genome-wide data from European and African human populations reveals that roughly 1% of the human genome shows the signatures of long-term balancing selection.
Further investigation of these regions reveals an enrichment for exonic and specifically non-synonymous SNPs, genes with high numbers of annotated transcripts, and a wide-range of gene functions, including immunity, oxygen transport, and reproduction.
This work has broad-reaching impact, first by providing a catalogue of genes for which we have evidence that selection played a role in maintaining genetic diversity. Additionally, this flexible and powerful statistic can be used to examine balancing long-term selection not only in additional human populations, but other organisms as well.
ASHG: Could you describe your research for us?
Dr. Bitarello: Broadly speaking, I am interested in all aspects of human population genetics and comparative genomics. More specifically, I have been interested in natural selection in the human lineage, the evolution of our immune systems and, more recently, the intersection between population genetics and precision genomics. I am particularly interested in understanding how phenotypes have evolved (neutrally or under selective pressures) and how those past events impact our adaptability today.
ASHG: What are your career goals?
Dr. Bitarello: I want to keep investigating interesting questions in human population and medical genetics by exploring the growing number genomes available, and developing better methods to make sense of these data. I would like to make contributions to the field without increasing (and, hopefully, reducing) biases in which groups of people are studied and benefit from biomedical advancements coming from genetics. I’d like to teach evolution, advocate for scientific education, and do as much scientific outreach as possible.
ASHG: Why did you choose genetics as your field of study?
Dr. Bitarello: Since my childhood I have been fascinated by biology, archaeology/paleontology, and human behavior in general. When I was 17, I read Luigi Lucca Cavalli-Sforza’s “Genes, Peoples, and Languages” and was hooked. It was then that I decided to study human population genetics to better understand our species.
ASHG: If you could pick three words that describe yourself, what would they be?
Dr. Bitarello: Thorough, detail-oriented, passionate.