IMAGINE a pub conversation that changed the course of medicine. That's where Professor Shankar Balasubramanian, along with his colleague Professor Sir David Klenerman, sparked a genomics revolution. Their groundbreaking work has made it possible to sequence the human genome in a single hour, paving the way for personalised healthcare and a deeper understanding of human diversity and disease.
As the two scientists huddled over their pints at the Panton Arms pub in Cambridge on a warm August afternoon in 1997, they weren't seeking to change the world. They simply wanted to watch DNA polymerase – essential for DNA replication – at work, assembling life’s building blocks. Instead, they stumbled upon something far more significant: a radically new way to sequence DNA.
“At the time, the Wellcome Sanger Institute nearby was determining the three billion bases of the human genome for the first time ever. The Human Genome Project underscored the need for a more rapid and cost-effective sequencing method. We realised that our work could be adapted to meet this need,” Balasubramanian later recounted.
In 2000, one human genome took over 10 years to sequence at a cost of more than $1 billion. Their new technology meant that a human genome can be sequenced in just one hour and for less than $1,000, meaning millions are sequenced each year.
The technology, now known as Solexa-Illumina Next-Generation DNA Sequencing (NGS), has driven advances in precision medicine, helping identify cancer mutations and diagnose rare genetic disorders. During the COVID-19 pandemic, NGS played a crucial role in tracking viral mutations and sequencing approximately 35,000 human genomes for UK studies.
“Most enter science driven by curiosity, hoping to make a difference,” Balasubramanian reflected while accepting the 2024 Canada Gairdner International Award. “I feel incredibly fortunate to see the impact of my work within my lifetime.”
The impact he speaks of is staggering. Today, the technology born from that pub conversation powers more than 90 per cent of global DNA and RNA sequencing.
It also underpins major research initiatives like the International Cancer Genome Project, the 100,000 Genomes Project, and Genome Asia 100K. In plant genomics, NGS offers high-throughput, cost-effective, and accurate data generation methods.
Yet Balasubramanian’s path to scientific stardom wasn’t always certain. Born in Madras (now Chennai) in 1966, he moved to the UK with his parents as an infant. Growing up in Runcorn, Cheshire, he nearly took a dramatically different turn after his university finals at Cambridge.
“I wasn't sure I had done well enough in my finals. In fact, I thought I'd messed them up,” he has said. “So, I considered a different direction – I was going to set up a chain of wine bars in America with a friend. Sometimes you don’t know exactly where your career is going – and that’s okay. Instead, I pursued a PhD, and that was a key turning point.”
After completing his PhD at Cambridge, he moved to Pennsylvania State University as a SERC/NATO Research Fellow. He returned to Cambridge in 1994 to establish his lab in the Department of Chemistry. His interdisciplinary research integrates organic synthesis, biophysics, molecular and cellular biology, and genomics, addressing key questions in biology and medicine.
Soon after their pub conversation, he and Professor Klenerman presented their concept to venture capitalists, leading to founding of their spin-off company Solexa in 1998. Within a decade, the US-based Illumina Inc. acquired the company for $600 million (around £315m then). As of February 2025, Illumina's market capitalisation stood at $15.9bn (£12.62bn), with revenues reaching $4.37bn in 2024.
“Today's sequencers can process trillions of bases per experiment, achieving over a million-fold improvement,” Balasubramanian explained. “In experimental science, such leaps are rare. This technology has transformed, is transforming, and will continue to impact life sciences and human health.”
Beyond Solexa, he co-founded Cambridge Epigenetix (now Biomodal) to develop tools for studying epigenetic modifications, which has the potential to lead to new diagnostic tools, therapies, and preventive strategies for various diseases. His team co-developed Chem-map, a tool providing groundbreaking insights into drug-genome interactions, with potential applications in cancer treatment.
His website modestly states: “Nucleic acids are fundamental to life. Our research is focused on the chemical biology of nucleic acids and employs the principles of chemistry and the molecular sciences to address questions of importance in biology and medicine.”
Yet for all his commercial success, Balasubramanian remains firmly rooted in research. “Being a scientist is a privilege, and I love what I do every day,” he has said. He holds joint appointments at Cambridge's Clinical School and Department of Chemistry, directing laboratories at the Cancer Research UK Cambridge Institute.
And he remains passionate about the fundamentals. During a recent lecture, he urged policymakers to prioritise funding for academic research. “Unless we strongly fund basic science, innovation is dead a few years down the line. Everything we’ve achieved wouldn’t have happened without early basic science funding.”
The accolades have poured in: knighthood in 2017, the Royal Society’s Royal Medal in 2018, election to the National Academy of Sciences in the US in 2024 and the Academia Europe in 2023. Alongside Klenerman, he has received the Millennium Technology Prize (2020), the Breakthrough Prize in Life Sciences (2022), and most recently, the Novo Nordisk Prize in 2024, among others.
His wife Veena Krishnan is a general practitioner, and they have two children, Sachin and Sashi.
“DNA is a far more interesting and mysterious molecule than was earlier thought,” Balasubramanian once remarked. Through his groundbreaking work in sequencing and ongoing research in nucleic acid biology, he continues to unlock those mysteries, pushing the boundaries of our understanding of life itself.
