Published : 2026-01-06
On 6 January 1997, Chinese scientists successfully constructed a complete physical map of the rice genome for the first time in the world. This was another major breakthrough for China in the field of life sciences.
Under the leadership of researcher Hong Guofan, after more than three years of arduous struggle, the National Centre of Gene Research at the Chinese Academy of Sciences (CAS) has achieved a world-first.
They successfully constructed a high-resolution physical map of the rice genome using the completed Bacterial Artificial Chromosome (BAC) library of the 12 rice chromosomes.
This major achievement has made a significant contribution to ultimately unveiling the mysteries of the genetic information of rice and crop breeding.
The rice genome is composed of 12 chromosomes with a total length of 430 million nucleotides, and the rice genome research programme includes three major components, namely: the construction of the genetic and physical maps of the rice genome, and the determination of the complete DNA sequence.
Countries carrying out rice genome research include Japan, the United States, India, South Korea, the Philippines, and others.
In the rice genome research programme, the physical map plays a pivotal bridging role. Based on the physical map, it is possible to lay the foundation for ultimately unravelling the mysteries of rice's complete genetic information.
Furthermore, this map also enables researchers to efficiently and systematically provide the essential genes and relevant information needed for agricultural genetic breeding through modern techniques, like map-based cloning.
The physical map of the rice genome constructed by China has the following three main characteristics:
First, its resolution (basic scale) is 120,000 nucleotides. Such a high resolution allows for the direct determination of the complete DNA sequence, while also simplifying the steps for obtaining desired genes.
Second, it contains 565 genetic molecular markers. As the physical distances between many of the markers have been measured, the speed of obtaining desired genes in cereal crops has been greatly accelerated.
Lastly, it contains nearly 100 common genetic molecular markers. These genetic molecular markers are common to the genomes of six major crops: barley, wheat, oats, maize, sorghum, and sugarcane.
Therefore, the construction of the physical map of the rice genome has had a significant impact on agricultural genetic breeding.
