Omar Cornejo

Postdoctoral Scholar - Bustamante Lab, Stanford University


August 19th, 2013. Our study looking at the role of natural selection shaping the genetic diversity in Natural populations of Mycobacterium tuberculosis is out in PLoS Pathogens!

August 16th 2013. I have joined the faculty of the School of Biological Sciences at Washington State University (Pullman, WA). Interested students contact me!

July 2013. The cacao genome and an example of its use to map complex traits like pod color is out in Genome Biology, check it out!


I am an evolutionary biologist in the lab of Carlos Bustamante at Stanford. My research is aimed to understand basic evolutionary processes that shape genetic variation in populations, and contribute to their adaptive evolution.  I am particularly interested in the evolution of microorganisms, and I like to combine population genetics/genomics analyses, phylogenetics, simple mathematical models and experimental work to address fundamental questions in their ecology and evolution.  During my PhD at Emory University, I worked under the supervision of Bruce Levin, combining experiments, simple models and sequence analysis to understand the impact of recombination in naturally transformable microbial populations, and the ecology and evolution of bacteriocins that kill the organisms that produce them.

  The increased availability of next generation sequencing has opened an incredible opportunity to ask questions about the demographic history and the genetic basis of adaptive evolution in microbes like Plasmodium and Streptococcus; two groups of organisms I continuously work on. Part of my research in the Bustamante lab has focused on the analysis of newly sequence bacterial genomes of the genus Streptococcus.

  Recently, I have developed a growing interest in the research of population genomics of cacao plants (Theobroma cacao), product of a growing collaboration with Juan Carlos Motamayor (MARS-USDA). Our interest is to employ re-sequencing data from cacao plants to study their demographic history and to identify the genetic basis of phenotypic traits that have been selected during its domestication and/or could be of potential interest for cacao breeders like resistance to diseases. Cacao is an important crop, with an enormous economic impact for the producing countries (that are generally developing economies), and the principal motivation behind this research does not come from the fact that I am venezuelan (and some of the best cacao in the world comes from Venezuela), but because we want to develop genomic resources to preserve cacao diversity and ensure a sustainable future for the crop. Also, we would like to develop cacao as a model system for how to map complex traits in long-lived tropical trees where generating multi generational mapping populations is not feasible.


Research Interests

Contact Information

Department of Genetics

Stanford University

300 Pasteur Dr,

Lane Bldg, Room L335

Stanford, CA. 94305

phone: 650-498-4751

e-mail: ocornejo(at)