Indian Initiative for Rice Genome Sequencing
Elucidation of the structure of DNA and the advent of recombinant DNA technology are high points of scientific achievements of the second half of the 20th century. These led to the realization of potential of biological sciences in determining the structure and function of the genetic determinants of traits which make one organism different from another or make a particular crop variety better. It did not take long to understand that many useful traits of crop plants are a sum of the activity of several genes and their regulators. Thus arose the need for high throughput approach to determine sequence of the whole genetic material of an organism and understand its functions. While first to be sequenced were genomes of viruses and organelles, in the last decade of the 20th century entire bacterial genomes have also been sequenced. Tremendous potential of new technology has led to sequencing of entire genomes of eukaryotes like yeast, Caenorhabditis, Drosophila, human beings and a model plant (Arabidopsis).
While the world food supply has more than doubled since the onset of green revolution, the task of providing food to additional 2.5 billion people, in the next 25 years, would have to be accomplished without significant increase in the area under cultivation. It is no more a hidden fact that the problem is compounded by the loss of land to urban development, degradation of productive land, decreasing yield of several conventional varieties, which contributed immensely towards green revolution, and loss due to the damage caused by various diseases and environmental stresses. It is, therefore, necessary to initiate an all-out strategy to understand the intricacies of the entire genome of at least one crop plant and its activity in order to acquire the capability to harness full genetic potential of crop plants. Rice is the staple food for more than one third of worlds population. It is estimated that to feed the growing world population total production of rice will have to increase by 60% in the next 25 years. Interestingly, rice has a small estimated genome size of ~ 430 Mbp (compared with ~16000 Mbp of wheat). Keeping in view its importance and feasibility, several leading labs of the world belonging to different countries (Brazil, Canada, China, France, Japan, Korea, Taiwan, Thailand, UK and USA) have already joined hands to sequence the entire genome of rice variety 'Nipponbare'. Such endeavor would lead to full structural information on rice genome and pave the way for functional and application genomics. The knowledge about rice genome would also be applicable to other cereals and millets in view of the synteny (conversation in the order of genes) and help develop the capability to utilize such knowledge for sustainable agriculture. With this view, Department of Biotechnology (DBT) and Indian Council of Agricultural Research (ICAR) have jointly laid down the foundation of the 'Indian Initiative for Rice Genome Sequencing' (IIRGS). The project is nucleated at the Department of Plant Molecular Biology (DPMB), University of Delhi South Campus (UDSC) and National Research Centre on Plant Biotechnology (NRCPB), Indian Agricultural Research Institute (IARI), New Delhi. As a part of international consortium for sequencing of the rice genome, IIRGS is assigned to deliver about 14 Mb of nucleotide sequence. India, through this project, has claimed a region spanning from 57.3 cM to 116.2 cM on the long arm of chromosome 11 of rice for performing high throughput sequencing, annotation of data and gene discovery. At an estimated cost of Rs. 48.83 crores (~ $10 million), two independent research facilities have been established at DPMB and NRCPB which are capable of performing high throughput sequencing as well as detailed annotation of the generated data. The map-based sequence of the rice genome was completed in December 2004 and published in Nature on August 11, 2005.