Professor Kellis’ expertise is in the areas of computational biology, genomics, epigenomics, gene regulation, and genome evolution. His group specifically seeks to understand how the genome sequence leads to the unique biology of each person, through understanding the functional building blocks of the human genome, their interconnections, and their association with disease and health phenotypes.
His work spans four areas: In the area of genome interpretation, he has developed comparative genomics methods to identify genes and regulatory elements systematically in the human genome. In the area of gene regulation, Kellis studies the regulatory motifs involved in cell type specification during development, their combinatorial relationships, and how these establish expression domains in the developing embryo. In the area of epigenomics, Kellis has uncovered chromatin signatures associated with distinct functions across multiple cell types, and sequence signals responsible for their establishment and maintenance. In the area of evolutionary genomics and phylogenomics, Kellis has studied the dynamics of gene phylogenies across complete genomes, the emergence of new gene functions by duplication and mutation, and has defined signatures for measuring selection within the human population.