Scientists develop mechanism to “switch on” genes

HYDERABAD - Scientists have worked out a mechanism to “switch on” genes introduced in a plant or an animal that has the potential for treatment of diseases like cancer, diabetes and Parkinsons as also for genetic crop modification. In the normal procedure, a gene, which has been introduced in plants or animals during gene therapy remains switched on. Thus, an insulin gene introduced in diabetics would keep producing insulin all the time, Subba Reddy Palli from the Department of Entomology, College of Agriculture, University of Kentucky told PTI at a sectional symposium at the 93rd science Congress here. With the gene switch technology, these genes can be made to express when needed, he said. In the technology, besides the desired gene, an element called “response element” and another called “receptor” are also introduced in the plant or animal. All three as a unit are called a “gene switch”. It has been found that a chemical called “ecdysone agonist”, which is an insecticide, attaches to the receptor of the gene switch (in case of plants) turning on the gene concerned, leading to the production of the compound for which gene is meant for, he said. The technology has potential for use in gene therapy for diseases such as diabetes and parkinsons, he said adding it can also be used for producing genetically modified crops and other plants, diminishing the risks involved in GM technology (as gene would function only when the chemcial is introduced). “While biotechnology and GM crops can be used to fight the problem of malnutrition, people are not very receptive of these due to fears of the genes used spreading to other species and the health risks involved,” he said. The technology is already being used to produce hybrids of corn and has the potential for use in case of BT cotton (in which an insecticide producing gene has been introduced into the cotton plant). However, there are concerns on account of insects becoming resistant to the BT toxin and a foreign gene consistently present in the cotton plant. The BT toxin gene can be switched by spraying the chemical during the time when insects’ density is more, he said. For use in animal genes, different chemicals would be needed to switch on the genes, he said. “When you gather for the next science Congress in 2007, you should be able to discuss the results,” Kalam told the gathering comprising scientists and officials. The President gave a seven-point research mission for promoting sustainable rural development through science and technology envisaging ushering in second green revolution, improving seed cotton productivity, water treatment facilities in rural areas, hill agriculture, floriculture and horticulture, increasing rice and wheat productivity and establishing solar power plants. Focusing his address on the theme ‘dynamics of rural development’, Kalam explained how science and technology could be used as a tool to achieve integrated and sustainable rural development and gave a detailed account of the success stories of pura clusters in Periyar (Tamil Nadu), Loni (Maharashtra) and Chitrakoot (Madhya Pradesh). Stating that pura model had helped generate rural employment using science and technology experiences from local colleges, he asked scientists and policy makers to take up the challenge of replicating these success stories across the country. There was a need to establish linkage to pura clusters by setting up domain service providers through pura nodal knowledge data centres, he said. Setting out a mission for the Science Congress, the President said, “Since ministers and secretaries from Central and State governments are present here, a decision can be taken to allot Rs 500 crore to develop 100 pura clusters”. "Source":[ http://www.checkbiotech.org/root/index.cfm?fuseaction=news&doc_id=11962&start=1&control=166&page_start=1&page_nr=101&pg=1].

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