Program in Computational Biology, Fred Hutchinson Cancer Research Center, Seattle, WA 98102, USA. mflawren@fhcrc.org|Program in Computational Biology, Fred Hutchinson Cancer Research Center, Seattle, WA 98102, USA. mflawren@fhcrc.org|Program in Computational Biology, Fred Hutchinson Cancer Research Center, Seattle, WA 98102, USA. mflawren@fhcrc.org