Scientists from Chinese Academy of Sciences (CAS) have independently finished the deep sequencing of oryza rufipogon genome firstly in China, obtaining the world's first highly heterozygous draft genome on August 2010.

China was one of the home of Asian cultivated rice, while oryza rufipogon is regarded as the wild ancestor of Asian cultivated rice and contains abundant excellent genes that are still mysteries to man. Because of their close genetic relationship, scientist have been mining oryza rufipogon for undiscovered excellent genes and looking for breakthroughs in rice cultivation.

Now this research was done by the group headed by Dr. GAO Lizhi, research fellow at CAS Kunming Institute of Botany. To have a deep sequencing and assembling of oryza rufipogon genome, GAO's group had turned to recently developed high-throughout sequencing technology and HPC-based bioinformational analysis of China Germplasm Bank of Wild Species.

Results from their research demonstrated that the genome size of oryza rufipogon was about 370 million base pairs, in other words, the oryza rufipogon genome contained about 370 million chemical units of DNA, or base pairs, with a total of 40,000 genes. The sequencing depth, that is, the total number of all the sequences reads or base pairs represented in a single sequencing experiment or series of experiments, was 70 times as large as the genome size. The sequencing results covered 92% of the oryza rufipogon genome with a gene coverage of over 90%, thus enhancing the reliability and replication of the findings. Now GAO and his colleagues had been drawing the detailed genetic map of oryza rufipogon. So far the detailed map of Nipponbare has been finished.

Oryza rufipogon is on the list of second-class state protection plants and is the most seriously endangered species among the listed three types of wild rice. Now with the draft and the detailed genetic maps of oryza rufipogon, things may change.

The genetic maps of oryza rufipogon are believed to facilitate the large-scale analysis and identification of the key functional genes in rice, providing unprecedented opportunity for mining and utilizing the huge excellent genes in oryza rufipogon with high-throughout technology. It will also be a driving force in rice variety improvement and germplasm innovation in China, enabling the scientists to have a thorough understanding of the origin of Asian cultivated rice and its domestication mechanism. It is especially true for Yunnan province which is visible for its rich genetic diversity of Asian cultivated rice.

Rice is the most important staple grain in China, providing food for over 80% of the country's population. Scientists believe that the genome maps may help boost the production of oryza rufipogon, one of China's major agricultural crops.