Rice has the smallest genome and was the first to be sequenced among cereals. Both the indica andjaponica genome have been sequenced and published by separate group in 2002 (Yu J et al. 2002 and Goff SA et al. 2002). The indica genome is 420 Mb in size and contains 32,000 to 50,000 genes, whilejaponica is larger, at 466 Mb, and contains around 46,022 to 55,615 genes.

International Rice Genome Sequencing Project (IRGSP) was established to map the japonica rice genome. The IRGSP adopted the "clone-by-clone shotgun sequencing strategy" so that each specific position on the genetic map was associated with a sequenced clone. In December 2004, the completed rice genome sequence was made available through the NCBI database.

Genome paper:

• Goff SA, et al. (2002) A draft sequence of the rice genome (Oryza sativa L. ssp. japonica).Science. 296(5565):92-100.
• Yu J, et al. (2002) A draft sequence of the rice genome (Oryza sativa L. ssp. indica). Science.296(5565):79-92.