Comparative analyses reveal the major fraction of functionally annotated gene models in monocots are located in recombination poor/very poor regions of the genome

Sequencing of the rice genome has allowed an in depth analysis of genome organization in a model monocot plant species. This has provided a powerful tool for genome analysis in large genome un-sequenced agriculturally important monocot species such as wheat, barley, rye, Lolium etc. Previous data has indicated that the majority of genes in large genome monocots are located towards the ends of chromosomes in gene-rich regions which undergo high frequencies of recombination.

Here we demonstrate that a substantial component of the coding sequences in monocots is localized proximally in regions of very low and even negligible recombination frequencies. The implications of our findings are that during domestication of monocot plant species selection has concentrated on genes located in the terminal regions of chromosomes within areas of high recombination frequency. Thus a large proportion of the genetic variation available for selection of superior plant genotypes has not been exploited. In addition our findings raise the possibility of the evolutionary development of large super-gene complexes that confer a selective advantage to the individual.