This meeting, organized by Richard Flavell (Ceres, Malibu, USA) and Rob Martienssen (Cold Spring Harbor Laboratory, USA), brought together a diverse group of speakers for a discussion of plant genome organization and the types of variation that exist between and within species. This report focuses on the consequences of this variation on phenotype, and the basis of this variation at the DNA and epigenetic | Meeting report Discovering the seeds of diversity in plant genomes James A Birchler and Kathleen J Newton Address Department of Biological Sciences University of Missouri Columbia MO 65211 USA. Correspondence James A Birchler. E-mail BirchlerJ@ Published 26 April 2004 Genome Biology 2004 5 323 The electronic version of this article is the complete one and can be found online at http 2004 5 5 323 2004 BioMed Central Ltd A report on the Keystone Symposium Comparative Genomics of Plants Taos USA 4-9 March 2004. This meeting organized by Richard Flavell Ceres Malibu USA and Rob Martienssen Cold Spring Harbor Laboratory USA brought together a diverse group of speakers for a discussion of plant genome organization and the types of variation that exist between and within species. This report focuses on the consequences of this variation on phenotype and the basis of this variation at the DNA and epigenetic levels. Keynote speaker Steve Tanksley Cornell University Ithaca USA provided a historical account of the molecular identification of quantitative trait loci QTLs . Those QTLs for which a molecular basis have been defined in his laboratory using tomato as a model system point to that fact that most such loci are regulatory in nature. This conclusion was bolstered in the talk by David Jackson Cold Spring Harbor Laboratory USA who reported that ramosai in maize a gene involved in floral branching has been identified as a transcription factor. This gene has also been shown to be a QTL candidate gene in mapping studies of populations that have different numbers of tassel branches. In addition the maize fasciated ear2 fae2 gene involved in determining kernel-row number is homologous to the CLAVATA2 floral development regulator in Arabidopsis and QTL analysis also shows an effect on floral development at this locus in maize. Ed Buckler Cornell University Ithaca USA reported that the maize Dwarf8 gene which encodes a transcription factor is .
