Given that Pennsylvania’s population has been relatively stable, the programme has collected data on the health of families, which is invaluable when tracking the roots of genetic diseases.
Since then, the programme has listed genetics conditions that can either be treated or prevented; therefore, viable to inform patients about. Currently there are 76 genes, linked to 27 conditions. Diseases with either no course for treatment or potential to prevent are not disclosed.
Currently, scientists have sequenced the exomes of more than 92,400 individuals, of which 85% have agreed to be contacted if an abnormality is detected in their DNA. In addition, more than 166,000 patients have volunteered and more than 400 have received notifications of a condition.
Could this be the forefront of diagnostic medicine?
First things first, is it cost effective?As of now, genome sequencing for an individual is estimated to be in the low thousands of dollars. Nonetheless, this cost can exponentiate with false positives and unnecessary follow-up tests.
Jason Vassy, a primary care physician at Harvard Medical School and colleagues recently followed 50 healthy adults receiving normal medical care, and another 50 who had 4,600 genes analysed, both at the cost of USD5,000.
Physicians ordered twice as many follow-up tests for the latter group. Therefore, Vassy believes providing such testing universally is only cost-effective if "it's a top-down approach to identifying high-risk individuals in a large population for whom they can provide a medical intervention".
Others say that the opportunity cost for mass screening procedures is too high because huge numbers of people have to be tested in order to find one with a possibly harmful gene.
Invasive follow-up tests on such people could also put them at risk of harm. It is also known that only a few population-based screening procedures have proved beneficial over time such as pap smears.
Unpredictable human behaviour is also a factor. In some cases, a carrier of a disease-causing mutation may do nothing with their diagnosis, in which case the test is a waste of money. Alternatively, an individual could overreact out of fear and consume too many health services: another large expenditure.
It is also possible that those who find out they are healthy, may take dangerous risks and neglect certain precautions such as mammograms. This could then instead increase medical costs.
Gene range and patient accessibility remain major concernsThere might not even be enough genes being tested for.
Michael Snyder, director of Stanford Medicine's Centre for Genomics and Personalised Medicine said that in a recent exome sequencing study he performed, he found variations in genes that he considers "medically actionable,” yet half of them are not included in Geisinger’s list. Furthermore, the medical centre does not inform patients of recessive genes, which could be a problem for any children the patient may have.
Many also believe that it is unfair that patients are not informed about conditions for which there is no treatment or prevention.
"Treatability may not be the only consideration people have regarding such information," says Lisa Parker, who directs the Centre for Bioethics & Health Law at the University of Pittsburgh in Pennsylvania.
Others are worried that people will not want to know their genetic odds.
For Lauren Corduck, knowing was a necessity. As an Ashkenazi Jew, she has 10 times the odds of having a cancer-linked mutation in the BRCA1/BRCA2 genes and many in her family have had various cancers.
“My jaw just dropped. How did I get to be the age of 45 without knowing this?” she exclaimed, referring to her 85% chance of getting ovarian cancer. “I’m well-educated. I live in the epicentre of world-class medical care.” Now in remission for breast cancer, she has started the non-profit Oneinforty to encourage testing and support families before after and during testing.
What are the benefits and does it have potential for the future?Geisinger also hopes to answer questions about how primary care doctors with little genetic knowledge could advise patients on their diagnosis, and how follow-up testing with at-risk could work. They also want to look into how much patients should be informed about their genetic make-up.
The testing is helping to save the lives of children, although currently only 2% to 3% of participants are enrolled in GenomeFIRST. For Dana Atkinson, the test showed that her son had the genetic disorder Long QT syndrome. Atkinson’s son is an avid football player and the condition is most likely to strike boys during intense exercise in their adolescence.
Her son is now taking B-blockers to reduce the risk of heart going haywire, and Atkinson herself has purchased an external defibrillator to jump-start his heart if it stops.
"I thank God for this programme, that this [mutation] was found and I'm not burying one of my kids,” she said.
Countries like Singapore and Israel are now examining Geisinger to inform their own genome-based medicine. MIMS
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Malaysian ovarian cancer study underway amidst other cancer research