Thanks to the recent completion of first ever human genome sequencing in India by scientists at the Institute of Genomics and Integrative Biology (IGIB), Delhi, India is finally knocking at the doors of personalised medicine. With this, medical treatment could be tailored to a patient?s distinct genetic profile. Sequencing can thus help predict which drugs will be useful for a particular patient.
Ever since the mapping of the human genes under the Human Genome Project in 2003, genomic discoveries are pointing the way to new drugs that disrupt processes at the molecular level and to tests that predict one?s risk for a disease. ?With these developments on accelerated mode, especially in India, we hope to see new drugs for diabetes, heart disease and a number of other diseases developed with the help of new genetic information,? says Anoop Misra, director, department of diabetes and metabolic diseases, Fortis Hospitals, New Delhi.
Predictably, Indian pharmaceutical companies are excited about the new opportunities. By using genomics data from the Indian Genome Variation initiative, Cadila Pharma has already launched a new drug formulation called Risorine for the treatment of tuberculosis. This is a fixed-dose combination product that has been approved in India for use as an anti-tubercular drug. In a multi-centric clinical trial conducted across India in patients with pulmonary tuberculosis, more than 90% of the patients treated with Risorine were cured with comparatively lesser side effects and better safety profile.
Ramesh Adige, president, Ranbaxy Laboratories says, ?Indians may respond differently to some diseases and drugs when compared with the Caucasian population since genetics plays a role in disease manifestation. With the un-coding of the Indian genome sequence, it may be possible to understand this response at a molecular level at least in theory at present and in due course, to design drugs that are better suited for the Indian population.? Additionally, he adds, the information may be used to understand the response of the Indian population to tropical diseases and diseases that are specific to India.
The human genome contains 3.1 billion base pairs, which describe every bodily function. The human genome sequence is like a map of the human body. ?Through the same tool, we can predict the chances of a particular disease affecting a population. We can also explore aspects like why certain drugs don?t affect certain people,? says IGIB director Rajesh Gokhale. Only five other countries?the United States, Britain, Canada, China and South Korea?have so far sequenced the human genome.
While the Human Genome Project took a decade to decode the human genome and cost $2.7 billion, scientists at IGIB finished the complete sequencing and assembly in much shorter time. Surojit Bose, co-founder of IIT Delhi drug discovery startup called LeadInvent says, ?The incredible speed with which the DNA mapping was done is significant as it can be used to sequence diverse Indian population and its variation, which can be helpful in understanding the diseases Indians are susceptible to. As supercomputers become common in institutes, we may expect more sequencing in future.?
Earlier this year, Council of Scientific and Industrial Research (CSIR) had successfully completed the genome sequence of a fish variety, called Zebrafish. While the Zebrafish genome was half the size of human genome, its sequencing earlier this year gave the CSIR the confidence to take up the challenge of human genome sequencing.
Virtually every human ailment, except trauma caused in accidents, has some genetic basis. Misra reveals that over the years, scientists have pinpointed some 1,700 genes linked to diseases; many of them are single gene mutations, for example, Huntington?s degeneration of brain.
?With the decoding of human genome, it may be possible to unravel in complex diseases like diabetes, high blood pressure, and coronary heart disease, which are common to India,? he adds.Another possible disease where this breakthrough may have an effect is in the study of cancer diagnostics.?Cancer is perhaps the most common genetic disease.
Effort can be made to understand the common genetic changes involved in diverse forms of cancers. If the fingerprints of such genetic changes are obtained, it may provide the rationale for the generation of a new era in cancer therapy, diagnostic and preventive strategies,? says Avadhesha Surolia, director, National Institute of Immunology.
Anand Anandkumar, chairman and managing director of Bangalore-based Cellworks Research points to the biggest concern: ?The breakthrough has taken place in the research arena. It remains to be seen how it is successfully transferred for commercial use.?