The biological blueprints for each one-of-a-kind individual are encoded in six billion DNA building blocks or base pairs. Given how each person is unique, it may come as a surprise that we share 99.9 percent of our genes with the entire human population. The remaining 0.1 percent—roughly six million base pairs—contain information that could determine our health, our risk of disease and how we respond to the environment or treatments.
The landscape of human genetic diversity is indeed a rich source of information for unlocking precision medicine’s full potential. Navigating this landscape, however, requires the use of maps: large genomic datasets that capture the full spectrum of this diversity. Only with a sufficiently detailed map will we be able to translate genetic research safely across different ethnic backgrounds.
We’re not quite there yet, however, considering that almost half of the global population is underrepresented in existing databases. To date, Asian genomes account for only ten percent of all recorded sequences. The divide is even more pronounced in South Asia which accounts for just one percent of all genetic data despite comprising 40 percent of the world population.
Hoping to bridge this chasm, the global precision medicine movement is well underway with a number of large-scale studies focusing specifically on Asian populations already in motion. To better serve their populations—which collectively form two thirds of the world’s population—countries across Asia are embarking on these database-building projects to fill in the much-needed details of the global genetic map.
Collecting, analysing and tracking genetic differences has life-saving potential; from helping design drug screening strategies to illuminating which patient groups are most at risk for developing certain medical conditions. Additionally, these genetic insights can help predict how patients are likely to respond to treatment. For instance, warfarin, a blood thinner commonly prescribed for cardiovascular conditions, is about four times more likely to cause adverse reactions in patients of Chinese, Korean, and Japanese ancestries, suggesting that these patients may require lower doses of the life-saving drug.
Likewise, lung cancer appears to strike Asians and Europeans differently, typically afflicting male smokers in European populations but showing up commonly in non-smokers of East Asian ancestry. One reason for this difference is that some East Asian lung cancer patients had tumours with much higher levels of proinflammatory genes, suggesting that East Asian patients could be treated with drugs targeting the immune system.
Understanding such differences means that doctors won’t have to resort to using trial-and-error to help their patients in the future. Instead, by feeding a patient’s DNA sequence into a genetic reference database they will be guided towards the most effective course of action with the highest safety margin.
But before patients can begin to experience the benefits of precision medicine, those reference databases need to be in place. In many of these database-building endeavours, researchers use state-of-the-art technologies such as next-generation sequencing and analytical platforms driven by artificial intelligence. These advances are slashing the time it takes to sequence and analyse human genomes from decades to days, accelerating discoveries around the associations between genetics and disease. Additionally, scientists can explore population structures and migration histories through genetic data, which can greatly assist in the design of even larger scale studies.
To date, nearly 40 countries worldwide have kickstarted precision medicine initiatives. China is positioning itself to be a global leader in the field, investing over US$9 billion to sample the genomes from its population of nearly 1.4 billion. Closer to home, Genomics Thailand aims to sequence the genomes of 50,000 Thais by 2023, adding much needed Southeast Asian representation to global databases.
Singapore, too, is committed to fast-tracking its citizens’ access to this new healthcare model. Accordingly, we have established Precision Health Research Singapore (PRECISE), an organisation that will work hand in hand with local patients, healthcare providers and government agencies in a collaborative manner to close the diversity gap around Asian genetics. Over the next decade, PRECISE will spearhead comprehensive local genomics studies and, importantly, boost public and industry engagement around precision medicine.
Centrally located in the heart of Southeast Asia, Singapore is uniquely suited for this program. The Island City is a melting pot of cultures and genomic diversity—over 5.8 million residents hailing from a multitude of regions in both Asia and beyond. The SG100K Project, for example, is an ambitious undertaking to understand Asia’s 4.5 billion people through the genomes of 100,000 Singaporeans from the three main ethnicities: Chinese, Malay and Indian. With this inherent diversity, Singapore is uniquely positioned to uncover comprehensive genetic insights that may be broadly applied to these populations.
The project is already yielding results: an earlier phase of the study—which sequenced the genomes of nearly 5,000 Singaporeans—discovered a whopping 52 million novel genetic variants from these participants alone. Armed with this data, PRECISE will leverage Singapore’s advanced healthcare information systems as well as secure, state-of-the-art local computing facilities to uncover what these variants mean and how they can influence health and well-being.
Ultimately, expanding the breadth of diversity in genomics for precision medicine isn’t just about programs and policies—it’s about people. By championing for education, accountability and transparency, PRECISE aims to promote inclusivity and lower the barriers to participation. We each hold a distinct piece of the genetic puzzle, which once complete, can reshape the future of how we manage and maintain good health.