Comparative linkage maps of the rice and maize genomes.

TLDR

Comparative linkage maps of rice and maize enable cross‑species interpretation of genetic and breeding data and lay groundwork for linking grass genetics. Genetic linkage maps were constructed for rice and maize using orthologous loci identified with a common set of cDNA clones. Conserved linkage groups covering over two‑thirds of both genomes were identified, with many chromosomes or arms showing near‑identical gene order and content, and more than 72 % of genes duplicated during ancient polyploidization remain in duplicate in maize.

Abstract

Genetic linkage maps have been constructed for the rice and maize genomes on the basis of orthologous loci detected with a common set of cDNA clones. Conserved linkage groups could be identified, which together account for more than two-thirds of both genomes. In some instances, entire chromosomes or chromosome arms are nearly identical with respect to gene order and gene content. The results also reveal that most of the genes (> 72%) duplicated during ancient polyploidization are still present in the maize genome in duplicate copy. The comparative maps of rice and maize provide a basis for interpreting molecular, genetic, and breeding information between these two important species and establish a framework for ultimately connecting the genetics of all grass species.