London surgeon John Hunter deliberately gave himself gonorrhea (and inadvertently, syphilis) in 1767 ? and suffered from effects of the diseases in his old age.
Jonas Salk dosed himself with his new polio vaccine in 1952 before testing it on anyone else. Down the years, scientists have inhaled poisonous gases, swallowed possible treatments for worms and detonated bombs at close range to assess the effects on their own bodies.
Now Michael Snyder has joined their ranks.
The geneticist didn't risk life and limb, but he did sacrifice his privacy ? inviting colleagues to sequence his DNA and track tens of thousands of markers in his blood over a period of 14 months, when he was sick and when he was well, ultimately crunching billions of measurements on the molecular details of his body.
Some of the results came as big, and not very welcome, surprises, uncovering, among other things, that he was at risk for Type 2 diabetes, and capturing the precise moments when the disease took hold in his body.
Snyder, who heads the genetics department at Stanford University's medical school, says the work is more than just a curiosity. He thinks that his experiment, published Thursday in the journal Cell, offers a taste of what medicine may be like someday for everyone.
Physicians talk often about "personalized medicine": the idea that therapies should be tailored to each patient's unique genetic and medical profile. Doctors already practice a sort of personalized medicine when they "type" a tumor to find the most effective chemotherapy drug. Someday, scientists like Snyder say, it will be a routine part of prevention too.
But if the gantlet his team ran is any indication, that day isn't upon us yet.
First, the researchers sequenced Snyder's genome ? the 6 billion letters of his DNA blueprint ? several times over, to assess his risk for various conditions. (And they sequenced Snyder's mother's genome as well, to learn which genes he got from each parent.) They drew Snyder's blood regularly to see how proteins, RNA and a swath of other chemicals in his body increased or decreased when he was in good health and bad ? his "omics" profile. They monitored his immune system and other health measures.
"Your genome shows what you're predisposed for. Your 'omics' profile tells you what's really going on," Snyder said. "This is a whole new level."
In all, Snyder said, the team crunched 3 billion measurements gathered over 20 time points, tracking close to 40,000 variables. The typical blood panel a patient gets at the doctor's office looks at about 20 variables.
Snyder's DNA didn't look terribly concerning, he said, though the team did find gene variants associated with basal cell carcinoma, high cholesterol and high triglycerides. One mutation he shares with his 83-year-old mother has been linked to a blood cell disorder called aplastic anemia, but neither has developed symptoms. He was more alarmed to learn he had versions of genes that put him at risk for Type 2 diabetes, which doesn't run in his family.
Snyder asked his colleagues to monitor his blood sugar closely. Intriguingly, his levels shot up about two weeks after he suffered a respiratory infection. The "omics" analysis showed that his body's ability to regulate glucose faltered during his illness, and he was ultimately diagnosed with diabetes.
It was the first time anyone had made a connection between viral infection and the onset of that disease, Snyder said.
He believes that if he hadn't performed this experiment on himself it would have been months or years before he would have discovered his diabetes ? perhaps time enough for complications of the disease to set in.
"If you find things early you can manage them," he said. "But if you find them late, it can be too late."
Luckily for him, simple measures such as improving his diet and losing some weight returned his blood sugar to normal.
He now plans to do similar profiles of 250 pre-diabetic patients to more rigorously observe what happens during the onset of diabetes.
Harvard geneticist George Church, who was not involved in the research, said Snyder's experience doesn't prove the infection-Type 2 diabetes link, but he says it's "potentially exciting" for future investigation.
Snyder, meanwhile, imagines a day when everybody will have their genomes sequenced and will be able to monitor their "omics" at home to manage their health, in a sort of smaller-scale version of his own experiment.
But before that can happen, teams like his will need to catalog the genomes, proteins, RNA and other chemicals of thousands of people along with their health information ? and then build a database describing how genes and changes in physiology relate to traits and disease.
The price of the process will have to come down, too. Even without factoring in man-hours and analysis, it cost thousands of dollars each of the 20 times the team pored over Snyder's blood results.
eryn.brown@latimes.com
jordan hill unlv sam young ncaa bracket ramon sessions portland trail blazers fab melo
কোন মন্তব্য নেই:
একটি মন্তব্য পোস্ট করুন