Bold new directions in personalized medicine
Genetic testing will let doctors predict, prevent disease
Personalized medicine has taken a great leap forward with the advent of affordable whole genome sequencing and new ways to characterize other molecules in the body. Rather than looking for a handful of known bits of genetic code associated with disease, the genome reveals all three billion characters in the code.
A new generation of medical tests could soon provide a molecular snapshot of the body, the health of most every major organ and the presence of disease even in its earliest stages, according to Pieter Cullis, a professor of biochemistry and molecular biology at the University of B.C.
Cullis is among the featured speakers at a public forum on the power and potential of personalized health care at the Vancouver Public Library today from 6 p.m. to 8 p.m. (Visit lsi.ubc.ca/talks for details and to RSVP.)
Q What can the genome tell us now?
A Your genome is the blueprint for your entire body and it can reveal the risk of getting disorders such as heart disease by identifying disease-related gene variants in the patient’s genetic sequence. In the case of purely genetic disorders, such as Huntington’s disease, it reveals the disease before symptoms arise with absolute certainty.
Q How are doctors using this technology?
A By identifying who is at greater risk of disease, doctors can intervene sooner and patients can take steps in their personal conduct to manage or even prevent the onset of disease. By analyzing the genetic code of cancer cells doctors can target therapies precisely to the mutations present in a tumour and determine in advance if a patient is likely to have a lifethreatening reaction to a drug before it is administered.
Q What’s around the corner?
A Analysis of the proteome — the entire set of proteins that can be created by our genetic instruction set — will potentially reveal the health of all of our organs in a single blood test. Our blood contains over 10,000 proteins — many of which leach from our organs into the blood — and can be used to assess the health of the organ and detect disease. Cancers shed proteins into the blood as well, which suggests such tools will have powerful early diagnostic value.
Q How is the practice of medicine going to change?
A Medicine is about to undergo a dramatic shift from detecting and treating illness once it has occurred to a preventive practice. Prognostic medicine will be about predicting and preventing disease. Cancer may be detected early enough to prevent its spread to the rest of the body. The genome of an unborn infant can be sequenced from cells found in the mother’s blood allowing doctors to detect genetic illness and the child’s risk for disease later in life well before a child is born.
Q How will patients be empowered? A
A whole genome sequence is a onetime risk analysis. Blood-borne proteins will provide a window on the health of our organs, information that could guide the day-to-day behaviour of patients, as well as their physicians. Doctors look for these proteins now with costly tests, one at a time, but a test could be devised to look for hundreds of such proteins all at once, a test that could be administered regularly and analyzed in hours for less than $100.