1 Faculty of Science, Department of Microbiology and Immunology, University of British Columbia, Vancouver Campus, Vancouver, Canada. Electronic address: michael.hunter@ubc.ca.
2 Humans and the Microbiome Program, Canadian Institute for Advanced Research, Toronto, Canada; Department of Anthropology, College of Arts and Sciences, University of Delaware, Newark, DE, USA. Electronic address: mmelby@udel.edu.
3 Faculty of Science, Department of Microbiology and Immunology, University of British Columbia, Vancouver Campus, Vancouver, Canada; Humans and the Microbiome Program, Canadian Institute for Advanced Research, Toronto, Canada; Michael Smith Laboratories, University of British Columbia, Vancouver, Canada; Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, Canada. Electronic address: bfinlay@msl.ubc.ca.