The case involves Michael Snyder, a geneticist who was both the lead author and the subject of a study on genomics reported in the journal Cell. The study began with the sequencing of Dr. Snyder’s genome, which showed that he was at high risk for Type 2 diabetes. Then the research team did extensive blood tests every two months or more, keeping track of 40,000 molecules in Dr. Snyder’s cells. About midway into the 14-month study, analyses showed that Dr. Snyder had indeed developed diabetes.
“My genome did predict I was at risk,” he said, “and because I was watching out, I detected the illness pretty early.”
The research team monitored the molecular changes closely as the disease developed. The illness was treated successfully while in its early stages, long before it might have been if Dr. Snyder had relied on a conventional visit to the doctor.
“This study is a landmark for personalized medicine,” said Dr. Eric J. Topol, a professor of genomics at the Scripps Research Institute in La Jolla, Calif., and author of “The Creative Destruction of Medicine.”
The study “is an unprecedented look at one person’s biology, showing what can be accomplished in the future,” he said. “This kind of granular information will one day allow doctors to manage illness in an altogether different and precise way.”
The business of personalized genomic medicine has long been expected to blossom as low-cost sequencing of the human genome becomes available from the many companies now working in the field. Currently, the price of human genome sequencing is typically about $4,000, said George M. Church, a genetics professor at Harvard Medical School. But within a year, he said, it could be down to $1,000 or even less.
Dr. Snyder, a professor and chairman of the genetics department at the Stanford University School of Medicine, said he wasn’t worried when his genome sequencing showed at the beginning of the study that he had a high risk for Type 2 diabetes.
“The disease doesn’t run in the family,” he said, “and I’m a touch on the thin side, so I don’t fit the usual stereotype.” Still, he kept a close eye on his glucose levels.
Then, in the midst of the study, he caught a cold. “I have two little kids,” he explained. “They get sick periodically,” passing their colds on to others.
It was this viral infection that apparently prompted the onset of diabetes, possibly because of stress. “The cold was a bonus,” Dr. Topol said. “We have not been generally associating viral infection with this type of diabetes. It is possible that the viral infection added additional stress.”
Dr. Snyder treated his diabetes through a change in diet — he eliminated desserts — and a doubling of his typical bike-riding regimen. He also returned to running. “It took about six months,” he said, “but my glucose levels came back to normal, allowing me to avoid medication.”
He said that because he typically schedules checkups with his doctor only once every two or three years, the disease would have long remained undiagnosed had it not been for the case study. “Probably no one would have caught my glucose shooting up for at least 18 to 20 months,” he said. “By then, I could have had damage.”
Dr. Snyder’s blood sample analyses were comprehensive. “We measured as many molecules as we could,” he said. “That meant we included my RNA, my proteins, my metabolites and my autoantibodies.” The research team analyzed about three billion data points.
Such exhaustive tests are not currently possible for most people, Dr. Topol noted. “Right now,” he said, “the price makes the procedure impractical.”
Dr. Snyder said the cost to collect molecular data from each blood sample was about $2,500 — which did not include the cost of analysis. But the price for tests similar to Dr. Snyder’s will also decline in the future, Dr. Church said.
And not all of the 40,000 molecules that Dr. Snyder tracked need to be included in every study. “The approach can be scaled down and particularized to the individual,” Dr. Topol said. “The team showed that it is feasible to manage and interpret data this way in the future.”
Dr. Church looks forward to the day when current research becomes a routine clinical procedure that combines inherited genomic information with analyses of RNA, proteins, metabolites and microbes in our bodies.
“One day, almost everything you wish the doctor would analyze will be measurable and interpretable,” he said. ‘It will be so much less expensive to do this because of technical improvements.”
Dr. Church is the founder of the nonprofit Personal Genome Project, which sequences and makes public the genomic and trait data of volunteers.
Dr. Snyder is a co-founder of a company, Personalis, in Palo Alto, Calif., that is developing software and other tools to interpret genomes after sequencing. Elaine R. Mardis, co-director of the Genome Institute at Washington University in St. Louis, said Dr. Snyder’s study points toward the joining of genomic medicine and standard medicine.
“The real message here is that conventional medicine doesn’t have to be replaced or supplanted by genomic medicine,” she said. “The integration of blood tests with genome sequencing adds so much granularity and precision.”