ABSTRACT:

Over the past decade, the ability to sequence genomes from both present-day and archaic humans (including our closest evolutionary relatives, the Neanderthals) has transformed our understanding of human history. Analyzing these genome sequences paints a picture of human history in which present-day humans migrated out of Africa but exchanged genes with multiple archaic human populations. I will describe computational methods that identify segments of DNA inherited from archaic humans that are surviving in our genomes today and how these maps of introgressed archaic DNA are providing insights into human migration and biology. Despite this progress, our understanding of the contribution of archaic introgression to populations in Africa remains limited, in part due to the challenges in obtaining ancient DNA in Africa. Leveraging recently developed computational methods that enable inferences about archaic populations without access to their genome sequences, we show that west African populations today inherit DNA from an as-yet-unidentified archaic ghost population.

I will discuss the implications of these results for our understanding of human evolution as well as the computational challenges that need to be solved in this endeavor.

BIO:

Sriram Sankararaman is an Assistant Professor in the Departments of Computer Science, Human Genetics, and Computational Medicine at UCLA. He is interested in developing statistical machine learning algorithms to make sense of large-scale genomic data and in using these tools to understand the interplay between evolution, genes and traits. He received a B.Tech. in Computer Science from IIT Madras, a Ph.D. in Computer Science from UC Berkeley and was a post-doctoral fellow in Harvard Medical School. He is a recipient of the Sloan, Hellman, Simons, and Microsoft fellowships, a NIH Pathway to Independence Award, as well as the UCLA Northrop-Grumman Excellence in Teaching Award.