Maize is the member of grass family (Poaceae) having a diploid genome size of 2.3 Gb with 10 chromosomes (2n=20) and a 2C genome content. Draft nucleotide sequence of the 2.3-gigabase genome of maize reported over 32,000 genes, of which 99.8% were placed on reference chromosomes. Nearly 85% of the genome is composed of hundreds of families of transposable elements, dispersed nonuniformly across the genome. Schnable et.al. 2009 sequenced the maize genome using a minimum tiling path of bacterial artificial chromosomes (BACs) (n = 16,848) and fosmid (n = 63) clones derived from an integrated physical and genetic map, augmented by comparisons with an optical map. Clones were shotgun sequenced (4-6X coverage), followed by automated and manual sequence improvement of the unique regions only, which resulted in the improved draft nucleotide sequence of the 2.3-gigabase genome of B73 maize reference genome version 1 (B73 RefGen_v1).
These were responsible for the capture and amplification of numerous gene fragments and affect the composition, sizes, and positions of centromeres.
More information can be obtained from maizesequence.org and maizegdb database.
Genome paper: Schnable PS, et al. (2009). The B73 Maize Genome: Complexity, Diversity, and Dynamics. Science 326, 11121115.
