2010stanforde25 michele dragoescu e25 project
TRANSCRIPT
By Michele Dragoescu E25, 2010
OverviewGenetic sequencing techniqueDirect to Consumer (DTC) Genetic Testing
Purposes and benefitsFinancial impactCurrent examplesPrivacy concernsTips for the future
What’s a genome, anyway?Review from class
Sequencing TechnologyQuick review of Solexa technique from class
Break down double stranded genomic DNA into fragments
Add single 3’ A overhangs, then ligate adapters that have 3’ T overhangs
Get 4 possible results
Continue E25 reviewAmplify fragments with two different
adapters using PCR. Heat them, make single stranded
Attach 5’ end to a solid surface that contains attached primers complementary to the adapters
Perform bridge amplification by solid phase PCR
Solid surface coated with primers
Still ReviewUse helicase to separate the strands. Now have
single stranded clustersCleave all of one type of the two adapter typesLeft with image:
Add fluorescently labeled terminating dNTP, DNA polymerase, and sequencing primer complementary to the adapter.
Final Steps to SequencingDNA polymerase adds only one
nucleotide because of the terminating group
A laser excites the fluorescent terminating group
The color indicates which base is presentTerminator removed, next base is read
Sequence many fragments with repeated sections, piece them together for full sequence
More Seq. Technologies454 Life SciencesIllumina, Inc. Pacific Biosciences
http://www.dnatube.com/video/3003/SMRT-DNA-Sequencing or PB homepage for demo video
Helicos BioSciences CorporationApplied Biosystems’ SoLiD system
Human Genome ProjectCompleted in 2003 and coordinated by the U.S.
Dept. of Energy and the NIHIdentified the 20,000-25,000 genes in human
DNADetermined the sequences of the 3 billion
chemical base pairsThen, cost about $1 billion. Goal: $1,000Stanford prof (Steve Quake) who sequenced his
entire genome, says he could use Helicos for $12,000 now and the $1,000 goal can be met within three years
GenotypingNot the same as full sequencingGenotyping - determining which genetic
variants an individual possesses. At 23andMe, they look at Single Nucleotide Polymorphisms (SNPs)
Sequencing - determining the exact sequence of a certain length of DNA. A given stretch may include some SNPs, in addition to regions that are constant
Direct to Consumer (DTC) GeneticsAt home genetic testing! Predict phenotype
based on genotype It’s controversial – because no doctor advice
involvedOften test for (1) genetic novelties (fun things
like wet or dry earwax), (2) ancestry, and (3) health risks
Expanding Market23andMeNavigenicsPathway
GenomicsThe March
2010 version of this chart is 14 pages long!
What is Pharmacogenomics?Predicting efficiency and safety of a drug on an
individual based on their genes and SNPs (regions of variability among humans)
PharmacoKinetics – how the body absorbs and metabolizes drugs
PharmacoDynamics - how the drug acts on the body: target region and mechanism of action
Even having the same SNP can lead to different phenotypes, depending on how many copies you have
Pharmacogenomic Database
WarfarinUsed to thin blood, prevent clots/strokes/heart
attacksVery difficult to dose--can’t predict based on size
of patientOverdose & underdose both dangerous
SNPs on two genes explain much of variability in dose needed (CYP2C9 and VKORC1)
Research set the dose using demographics + genetics
Stanford Prof. Russ Altman’s (creator of PharmGKB) dosing algorithm now on FDA labels for warfarin
Health spending $4.3 trillion or 19.5% of GDP by 2017
The global market for personalized medicine is expected to grow to $452 billion in 2015 (Pricewaterhouse Coopers)
The core diagnostic and targeted therapeutic segment of the market is presently estimated at $24 billion expected to grow by 10 percent annually,
reaching $42 billion by 2015
Personalized medicine - a good investment
Current EventsWalgreens is awaiting FDA approval to sell
genetic testing kitsThe kit would be $20, with a vial and envelope to
ship off to Pathway GenomicsThe report would cost $79 to $179, depending
on the type of test Signals trend of ease of access of genetic
testingNo doctor intervention is required, and
scientists worry that consumers will misinterpret the tests, which don’t give definite diagnoses
Genetic Testing In the NewsUC Berkeley is asking the Class of 2014
to voluntarily submit sample for genetic testing for susceptibility to too much alcohol, dairy, and not enough vegetables
Freshmen get two bar code labels, one to put on the sample and one to keep.
After genotyping, results will be posted online using only the bar code identification to protect privacy
Privacy ConcernsToo many SNPs revealed lead to the ability to
figure out the identity of the individual in question
Privacy ConcernsIncreasing number of genetic databases exist
to support research, and they have long stretches of DNA.
Of 1,000,000 locations in genome where people may differ, only 60-100 need to be measured to give a unique fingerprint of a person
If this information is associated with phenotype data, it can be a risk to thestudy subjects
Past Issues of Re-IdentifiabilitySperm donor in UK
A teenager used some genetic information, general region of country to look up the identity of his father (a sperm donor)
Is the father now responsible for playing a role in his son’s life?
Governor of Massachusetts used public records (public health, voter, DMV) to prove she could trace identities
Patients with rare diseases are easily identified (public health records, Medicaid billing, voter, DMV)
The FutureThe world is eagerly awaiting the future of
pharmacogenomics and personalized medicine
Industry experts are making their predictionsAnd also offering some words of advice
Key FindingsExecutive summary of Price Waterhouse Cooper
The blockbuster model currently pursued by the pharmaceutical industry won’t disappear any time soonBlockbuster means huge costs, but huge rewards
Unexpectedly, stratifying prospective patients through pharmacogenomics can increase a product’s marketEven though you’re making a smaller market,
you’re can reduce advertising and dominate the niche
More findings on pharmacogenomics futureRegulatory and reimbursement structures
related to pharmacogenomics are in placeBoth the FDA and 3rd party payers are drafting
policiesPharm. will give life science companies greater
options for leveraging their skills, expertise, and discoveries
Pharm. will likely be driven by a successful, compelling productThe first high-profile pharmacogenomics product
will probably be related to cancer
Suggestions for FutureNature paper compares two DTC genetics-
testing companiesCraig Venter one of the authors
For seven diseases, 50% or less of the predictions of two companies agreed across five individuals
Paper advises: Companies should communicate high risks better and test for drug response markers
Community should study markers in allethnicities and look at behavior after tests
Bibliography "- Genetics & Public Policy Center || News & Events || News Releases || Updated Chart of Direct-to-
consumer Genetic Testing Companies Available." - Genetics & Public Policy Center -. The Genetics and Public Policy Center Johns Hopkins University Berman Institute of Bioethics, 9 Mar. 2010. Web. 24 May 2010. <http://www.dnapolicy.org/news.release.php?action=detail&pressrelease_id=137>.
Colliver, Victoria. "Ethics of UC Berkeley's Gene Testing Questioned - SFGate." Featured Articles From The SFGate. Web. 24 May 2010. <http://articles.sfgate.com/2010-05-21/bay-area/20907654_1_genetic-testing-test-results-testing-kits>.
Justin. "Healthcare Costs under the Microscope of Personalized Medicine « TheOTCInvestor.com." TheOTCInvestor.com. Web. 24 May 2010. <http://theotcinvestor.com/health-care-costs-under-the-microscope-of-personalized-medicine-715/>.
Ng, Pauline C., Craig J. Venter, Sarah S. Murray, and Samuel Levy. "Access : An Agenda for Personalized Medicine : Nature." Nature Publishing Group : Science Journals, Jobs, and Information. J. Craig Venter Institute, Oct. 2009. Web. 24 May 2010. <http://www.nature.com/nature/journal/v461/n7265/pdf/461724a.pdf>.
Perton, Marc. "FDA Investigating Walgreens Genetic-Testing Kits." The Consumerist. Web. 24 May 2010. <http://consumerist.com/2010/05/fda-investigating-walgreens-genetic-testing-kits.html>.
Wade, Nicholas. "The New York Times Log In." The New York Times - Breaking News, World News & Multimedia. Web. 24 May 2010. <http://www.nytimes.com/2009/08/11/science/11gene.html?_r=3&hp>.
"What Is the Difference between Genotyping and Sequencing? | PPH." The Mission of Palomar Pomerado Health Is to Heal, Comfort, and Promote Health in the Communities We Serve. Web. 24 May 2010. <http://www.pph.org/PPHContentPage.aspx?nd=44>.
Russ Altman’s talks on pharmacogenomics Pharmgkb.org