January 21, 2009

DTC genetic tests I

Direct-to-consumer (DTC) genetic tests: is this the medicine of the future? (Part I)

New year new millennium and new technologies. What did you imagine for your future? The Genetics is in front of our door and we don’t have all the responses to approach this vertiginous advance. Direct-to-Consumer (DTC) genetic testing is a type of genetic test that is accessible directly to the consumer without having to go through a health care professional. Usually, to attain a genetic test, health care professionals acquire the Informed Consent and order the desired test. DTC genetic tests, however, allow consumers to bypass this process and order one themselves.

That is the question: are you ready to be your own doctor?

There are a variety of DTC tests, ranging from testing for breast cancer alleles to mutations linked to cystic fibrosis. Benefits of DTC testing are the accessibility of tests to consumers, promotion of proactive healthcare and the privacy of genetic information. Possible additional risks of DTC testing are the lack of governmental regulation and the potential misinterpretation of genetic information.

What we are talking about? Well, I tried to organize this DTC in 5 mai
n groups:

1. Genetic risk disease test
2. Personal Genome decoded
3. Ancestry assessment

4. Home paternity testing
5. Miscellaneous

DTC for Genetic risk disease

These genetic tests scan of DNA mutations to calculate your individual genetic risk for a specific disease. DTC genetic tests include a spectrum of high and low penetrant genes, such as the identification of single nucleotide polymorphisms (SNPs) associated with cardiovascular disease, breast, ovarian, colon and uterine cancers, osteoporosis, detoxification defects, metabolic deficiencies, and immune system defects. Penetrance is the probability that a gene or genetic trait will be expressed. Both gene penetrance and the associated risk, which may be linked to potentially harmful or beneficial effects, vary. Such risk can sometimes be affected by environmental and lifestyle factors.

Even if a person has a genetic mutation associated with a particular disease or condition, this does not necessarily predict when it will develop, if at all, or its severity. This variability and the fact that a number of the specific disease associations have not been established, makes interpretation of many DTC genetic tests difficult and their clinical utility less than clear. Actually, tests are available in two main classes: for gene
ric screening of diseases or specific diagnostic of a disease.

Having one’s complete genome sequenced is far more thorough than the scans done by companies such as 23andMe (also in Mountain View) and DeCodeMe of Iceland. These companies offer direct-to-consumer testing of a person’s DNA for between $399 and $995.

DeCODEme offers complete scan that explore your genetic risk factors and keep a vigilant eye on your prospects for prolonged health. By analyzing an unparalleled one million genetic variants, the complete scan is the most accurate, advanced and comprehensive test of its kind. The Complete Scan focuses on medical conditions that can either be improved by altering your lifestyle or to have better treatment options if caught early. They offer updates to your profile as new genetic variants are discovered. The conditions we cover are categorized into these main groups: cancers, blood diseases, bones, joints and muscles, brain, nerves and vision diseases, lungs and breathing problems, heart and circulation, digestive and metabolic system diseases, skin, hair and nails.

23andMe company offers scan about conditions and traits for which there are genetic ass
ociations that have a substantial influence on a person's chances of developing the disease or having the trait like age-related macular degeneration , alcohol flush reaction, bitter taste perception, Bloom's Syndrome, Celiac Disease, Crohn's Disease, Cystic Fibrosis, earwax type, Eye Color, G6PD deficiency, Glycogen Storage disease Type 1a, Hemochromatosis, Lactose intolerance, Malaria Resistance, muscle performance, Non-ABO Blood Groups, Norwalk virus resistance, Parkinson's Disease, prostate cancer, Psoriasis, resistance to HIV/AIDS, Rheumatoid Arthritis, Sickle Cell Anemia & Malaria Resistance, Type 1 Diabetes, Type 2 Diabetes and venous thromboembolism.

DNA Direct now offers Colon cancer screening essay (ColoSure™) and alpha-1 antitrypsin deficiency essay (AT-1), in home that includes a personalized report, a letter for your doctor, and toll-free support by $330.00.

ATLAS Sports Genetics
is offering a test for ACTN3, otherwise known as the speed gene. They charge $149 for the Atlas First. For $249, you get the Atlas Plus kit. It tells you how high your kid jumps. The ACTN3 test is the preeminent example of a novelty genetic test. It tells you nothing useful. I mean, if they had a genetic test that ind
icated something useful about athletic ability that would be one thing. The ACTN3 test gives something of an indication about whether your muscles are more suited for sprinting or endurance.

Navigenics scans your DNA for genetic risk markers associated with both common and uncommon health conditions. They offer a membership to Navigenics Health Compass genetic testing service that include an analysis of your genetic predisposition for a variety of common health conditions, and the information, support and guidance to know what steps you can take to prevent, detect or diagnose them early, a scan of your whole genome, carried out by a government-certified laboratory, that captures data on 1.8 million of your genetic risk markers. The genetic testing service is $2,500 for all the features above, including the first year's subscription, with an ongoing subscription rate of $250 per year for continuous service.

What do you think? It’s very impressive, is it?

We need to understand the truly important of these technologies, what is the real benefit for a common individual? Can we apply widely this tests? It Still so much wool to be cut!

Personal Genome decoded

Gene-testing companies will sell you a near-complete personal view of your own DNA for somewhere between $100,000 and $350,000. A year ago it cost $1 million. Five years ago, the cost of the first complete human genome was $2.7 billion. Some of these companies are:
Knome, Massachusetts-based, offer Knome's Complete Genome Sequencing and Analysis Service, the most comprehensive genome analysis available on the market today. Knome, currently offers a full genomic sequencing for $350,000. They analyze over 1,500 genes and over 400 genetic conditions too. Additionally, they conduct carrier screening for rare genetic disorders and generate a pharmaco-genomic profile to determine how your individual genetic make-up might influence your response to specific therapeutic agents.

Complete Genomics based in Mountain View, California—says that, come next spring, it will be able to tease out virtually every nucleotide—the A’s, C’s, T’s and G’s that make up
DNA—inside you or me for a mere $5,000. This company is now building the world’s largest commercial human-genome-sequencing center. It expects to sequence 200 genomes per day by the end of 2010.

They remain important aspects to discuss of DTC like the regulatory issues, intellectual property considerations, interaction between biotechnology, molecular diagnostic, and pharmaceutical markets, the role of physicians in helping patients interpret results from direct-to-consumer (DTC) genetic tests, effect of DTC market on molecular diagnostic laboratories, patient and consumer security, public relations and business strategies to optimize public perceptions of DTC genetic testing.

That these genetic tests are offered directly to consumers, outside the parameters of the medical or clinical genetics context, raises ethical concerns. Four principles from bioethics-non-maleficence, beneficence, respect for autonomy and justice-offer a way of framing and critically examining the ethical issues.

More about this...soon!

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