India can become a vaccine leader as research scientists in the country are in the process of producing indigenous vaccines that are affordable to the country's population. When the pharmaceutical sector worldwide does not consider vaccine production as an economically viable project, India is proving to the global market that vaccines will be its next forte, said Prof. G Padmanabhan, former director, Indian Institute of Science during the plenary session on 'Emerging Technologies in Biosciences and Genomics Research' at the 90th Indian Science Congress held here in Bangalore.

In his key note address, Prof. Padmanabhan pointed out that microbial genomics and the human genome project have opened up several opportunities for new drugs, vaccines, and diagnostic procedures for the two dreaded diseases- tuberculosis and malaria that are increasingly turning to be drug resistant in India.

Scientists are now dwelling on the theory of a classical approach, which is a gene-by-gene process to arrive at drug targets for tuberculosis and malaria. Genomics is looking at large-scale pathways for purposes of disease surveillance, identification of diverse bacteria and evolution of the genes.

BGG which was the only drug to control tuberculosis in children, is no longer successful to cure or control pulmonary tuberculosis in adults. Under the Jai Vignan programme the scientists are now using BCG as a primary path to discover the genetically engineered genes, said Prof. Padmanabhan.

Delving into the research, Prof. Padmanabhan said, "We have animal models to mimic the situation of drug resistance where animals with low nutrition levels are selected for tests. A typical case being the frog infection model where targets are used to develop the dormant bacteria. The Council of Scientific and Industrial Research (CSIR) has developed an indigenous NIMITLI gene target for drug resistance."

In the case of newer drugs for malaria, the human genome project increases the chances to tackle the parasite gene expression and study the causes of drug and insecticide resistance. The scientists have targeted 5,000 genes. The genome sequence study is on in the area of blood cell haemoglobin degradation to block the parasite as chloroquine, which is the cheapest drug is turning drug resistant and scientists are now looking for an alternative. In a study funded by the department of biotechnology, government of India out of the 50 samples collected from all over the country, 48 blood samples are drug resistant and only two samples are sensitive to chloroquine. Another finding is that there is a higher concentration of odorant genes in some sections of the population which is the cause of frequent mosquito bites andstudies are on to block the odour receptors in the insects.

Currently, the scientists are looking at the viability of using the present TB drugs like INH and rifampicin to cure malaria. A lab experimentation revealed that a strain of malaria in mice has cured up to 80 to 90 per cent. In another mouse model with Plasmodia berghei, the scientists were able to achieve a cent percent cure for malaria when the two TB drugs along with co-trimazole, he informed.