image: This is the maize B73 reference genome (B73 RefGen_v1): Concentric circles show aspects of the genome. Chromosome structure (A). Reference chromosomes with physical fingerprint contigs (11) as alternating gray and white bands. Presumed centromeric positions are indicated by red bands (31); enlarged for emphasis. Genetic map (B). Genetic linkage across the genome, on the basis of 6363 genetically and physically mapped markers (14, 19). Mu insertions (C). Genome mappings of nonredundant Mu insertion sites (14, 19). Methyl-filtration reads (D). Enrichment and depletion of methyl filtration. For each nonoverlapping 1-Mb window, read counts were divided by the total number of mapped reads. Repeats (E). Sequence coverage of TEs with Repeat Masker with all identified intact elements in maize. Genes (F). Density of genes in the filtered gene set across the genome, from a gene count per 1-Mb sliding windowat 200-kb intervals. Sorghum synteny (G) and rice synteny (H). Syntenic blocks between maize and related cereals on the basis of 27,550 gene orthologs. Underlined blocks indicate alignment in the reverse strand. Homoeology map (I). Oriented homoeologous sites of duplicated gene blocks within maize. This image relates to a paper that appeared in the Nov. 20 issue of Science, published by AAAS. The study, by Patrick Schnable of Iowa State University in Ames, Iowa, and an academic research consortium, was entitled, "The B73 Maize Genome: Complexity, Diversity, and Dynamics." view more
Credit: [Image courtesy of <i>Science</i>/AAAS]