Yuk-Ming Dennis Lo

Yuk-Ming Dennis Lo arrived in Cambridge, England, in October 1983, on the brink of one of the coldest winters in British history. Traveling with more luggage than he could carry, the 20-year-old took a taxi from the coach station to nearby Emmanuel College, which would be his home during his three undergraduate years at Cambridge University. Within weeks, the spires and towers of the ancient university town were covered in snow. Walking through the bitter, blustery streets to class was a trial for Lo, who was born and raised in sultry Hong Kong. Inside the lecture halls, he faced another challenge. He had been learning English since he was four, but his professors and classmates spoke so fast and with such a dizzying array of accents that they created their own kind of blizzard. Then there were the tutorials, which happened three to five times a week, each lasting 60 minutes. “That's one hour when you have to face a very clever professor,” said Lo, professor of chemical pathology, Li Ka Shing Professor of Medicine, and director of the Li Ka Shing Institute at the Chinese University of Hong Kong. One day, early on, his professor asked Lo a question. Lo gave a technical answer, drawn from his textbook. His professor shot back: how do you know that? “At the time, I felt that was a strange question, so I told him, ‘The book said that,'” said Lo. “What he meant was, ‘How do you know the book is correct? What is the experimental evidence?'” That tutorial marked a turning point for Lo. He would take his professor's lesson—doubt dogma, revere data—to heart, nurture it, and develop it into a credo and a passion. In 1987, as a 24-year-old medical student, he had the idea that fetal cells might be …