Bangalore: If the developing world wants to provide effective health care to its people, it must use genomic medicine based on the genetic variation of individuals and sub-populations, where India, Mexico, Thailand and South Africa have already set the ball rolling, says a new Canadian study in Friday’s issue of Nature Reviews Genetics, or NRG.
“Developing countries cannot rely on the altruism of western economic interests to address specific health needs of their populations. Purchasing health products from the West will only contribute to continued dependency…on wealthier northern neighbours,” said lead author Abdallah S. Daar, professor of public health sciences and co-director of McLaughlin-Rotman Centre for Global Health, University of Toronto.
The two-year, four-nation study included the Indian Genome Variation (IGV) consortium, which, earlier this year, announced the first large-scale database of genomic diversity in the Indian population. In its first phase, IGV studied 405 single nucleotide polymorphisms (DNA sequence variation in one of the four nucleotides) in 75 diseases among 1,871 people from 55 populations. Now, in the second phase, Indian researchers have analysed 580 samples from 26 population groups and looked at 1,000 genes aiming to find gene specific variations and possible drug targets.
Some ongoing genomic medicine research developments (PDF)
“The overall (gene) clustering remains the same (from first phase study); this is important data as it’ll help us look for side effects of drugs in specific populations,” said Samir K. Brahmachari, co-author from India in the NRG study, director general of the Council of Scientific and Industrial Research, and one of the lead researchers of IGV. This information will allow drugs with expired patents to be tailored for population groups that have the lowest risk of side effects
To begin with, IGV has taken the low-cost epilepsy drug phenytoin, which costs about Rs800 for one-year therapy, but is reported to have side effects in at least 10% of the population. “We have undertaken a project, led by Gauri Devi, an epilepsy expert and former director of Nimhans, to look for biomarkers and design a diagnostic to identify people who are resistant to this drug,” said Brahmachari.
Aiming at a predictive population therapy database, IGV is currently conducting population-based screens for susceptibility to certain diseases, including asthma, diabetes, neuro-psychiatric disorders and malaria as well as variation in drug metabolism. It is found that 13% of the population does not respond to 30 essential drugs in northern India.
IGV has also embarked on an initiative to integrate Ayurveda, the traditional Indian system of medicine where individual variations were described 4000 years ago, with genomics and is calling it Ayurgenomics. The findings are published in September issue of the Journal of Translational Medicine.
Ayurveda’s classification of phenotypes (physical traits), allows biologists to uncover genes that may contribute to system-level differences in normal individuals which could point to differential disease predisposition. “We are trying to see if they (genetic profile, Ayurvedic classification, biochemical data) can be correlated,” said Brahmachari. For the first time, an Ayurvedic analysis based on questionnaire involving 1,500 people has been done and if this method proves effective, then millions of people can be analyzed, he noted.
Although IGV efforts can contribute to reducing healthcare costs and improve public health, argue researchers, since it is not linked to the Union ministry of health, there is a gap between R&D and eventual delivery of local health benefits. The study also finds that the Indian private sector is “either uninterested or not prepared to foray into genomic medicine”.
Another bottleneck lies at the regulatory front where the Central Drugs Standard Control Organization, or CDSCO, in New Delhi has not yet established any guidelines for clinical trials or therapeutics that rely on population differences, genomic sciences or pharmacogenomics.
“It is important at this stage to look at the bigger picture, not just personalized medicine,” said Daar in an email. The capacity for genomics research built through current initiatives will play a very large role in Indian public health, for example, in tracking infectious disease outbreaks such as polio and bird flu, he added.
Mexico has calculated that genomic medicine can reduce diabetes management costs between 2010 and 2025 by 36%. “India is faced with an epidemic of diabetes and could save even more,” Daar said.