(Image credit: medicineworld.org) 

This week b5 media’s Health and Wellness channel is focusing on celebrities health.  Our focus is not on ‘tittle tattle’  and hot gossip about Angelina, Brad or ’Tomkat’ but rather a serious look at health issues that high profile individuals share with all of us. 

In the genetics world, our ‘celebrities’ are the likes of Craig Venter and James Watson - pioneering geneticists but basking in the eye of the media.

The race to sequence genomes has resulted in some major PR, particularly for Craig and James. 454 is sequencing James Watson’s genome and Craig has announced some of his results in PLoS.  TV star Larry King, cosmologist Stephen Hawking, Google co-founder Larry Page, Microsoft co-founder Paul Allen and junk bond trader Michael Milken have all paid a vast sum of money to have their genomes sequenced.

However, this is causing a degree of discomfort within the scientific community.  They are worried that only the rich will benefit and it’s sending out the wrong messages to the public.

I have a different perspective.  Research has to start somewhere.  The very rich have always been the first to buy pioneering technology whether it’s a car, the latest computer or mobile phone.  Their money will assist  in further driving down the cost of the technology to such a price that will be affordable to us mere mortals.

Elaine Warburton  www.geneticsandhealth.com

 (Tasmanian Tiger - photo credit www.bbc.co.uk/news)

Using transgenic mice, Australian and American researchers have shown that they can “resurrect” a snippet of DNA from the genome of an extinct animal — the Tasmanian tiger — and test its biological function in a living animal.   The last Tasmanian Tiger died in an Australian zoo in 1936 having been hunted to extinction.

Dr Andrew Pask, of the Department of Zoology at Melbourne University, who led the research, said it was the first time that DNA from an extinct species had been used to carry out a function in a living organism.

“As more and more species of animals become extinct, we are continuing to lose critical knowledge of gene function and its potential,” he said.  “Up until now we have only been able to examine gene sequences from extinct animals. This research was developed to go one step further to examine extinct gene function in a whole organism.”

The team extracted DNA from some of these specimens, and injected a gene involved in cartilage formation into developing mouse embryos.  The DNA functioned in a similar way to the equivalent gene in mice, giving information about the genetic make-up of the extinct marsupial.

“At a time when extinction rates are increasing at an alarming rate, especially of mammals, this research discovery is critical,”said Professor Marilyn Renfree, also of the University of Melbourne’s Department of Zoology.

“For those species that have already become extinct, our method shows that access to their genetic biodiversity may not be completely lost.”

Elaine Warburton  www.geneticsandhealth.com

Osteoporosis 

(Image source: www.soylabs.com) 

An extensive genome-wide search has been undertaken to find the genes linked to osteoporosis and fracture. Five regions of interest have been identified that appear to warrant further scientific investigation.

The Garvan Institute for Medical Research collaborated with the Icelandic genetics company, deCode, in a project that looked at 1500 women from Garvan’s Dubbo Osteoporosis Epidemiology Study as well as more than 12,000 women from Iceland and Denmark.

The collaborative study examined more than 300,000 such markers and found 12 that were linked to bone mineral density and 6 linked to fragility fractures. Some of these SNPs are close to genes that are already known to be associated with osteoporosis.

The next step will be identifying what those genes are and how they might contribute to scientists understanding of osteoporosis and its prevention.

http://www.decode.com/News/2008_04_29.php

Elaine Warburton  www.geneticsandhealth.com
 

(Photo: Breast cancer cell , courtesy www.hopeforcancer.com)

Scientists believe they have identified a gene that may be able to limit the growth of breast cancer tumors.

The US National Cancer Institute, led by geneticist Kent Hunter found in tests on mice that tumors containing the bromodomain 4  or Brd4 gene ended up 10 times smaller than ones that did not.

In typically growing cells, Brd4 is a nuclear protein that’s associated with chromatin. It apparently influences DNA replication and cell cycle progression. Because of its previously identified physical interaction with an invasiveness-suppressing GTPase activating protein called Sipa1, Hunter and his colleagues decided to delve into Brd4’s role in breast cancer.

The team then carried out research into 1,240 patients, split between five separate groups.  They found those with the Brd4 gene had much better survival rates - in some of the groups it was nearly double the rate than those without the gene.

Using Affymetrix GeneChip Mouse Genome 430 2.0 arrays, Hunter and his team found the Brd4-mediated gene expression profile or signature in mice. Nearly 150 classes of genes seem to be influenced by Brd4 expression — including some related to cellular processes such as cell cycle progression, chromatin structure, cytoskeletal remodeling, cell adhesion, and extracellular matrix functions.

They mapped these onto human Affymetrix datasets in the National Center for Biotechnology Information Gene Expression Omnibus as well as the Dutch Rosetta cohort, which used a different microarray platform. Several hundred human genes had expression profiles that were similar to those in Brd4 expressing mouse models. In addition, the level of Brd4 activation could predict survival for all five data sets.

It also provided clues about survival in other patient populations such as those whose cancer had not spread to their lymph nodes and those with estrogen-receptor-positive tumors.

Though the results are still preliminary, they suggest that this work may help doctors better predict each patient’s breast cancer progression. In addition, the authors noted that they are currently assessing SNP data to determine whether Brd4 polymorphisms also influence breast cancer progression and prognosis.

“The results of this study and other work in our laboratory suggests that people with inherited differences in Brd4 and the proteins that it induces have a genetic predisposition for developing cancer metastasis,” Hunter said. “A better understanding of this gene may lead to improved methods of diagnosing and treating cancer.”

Elaine Warburton  www.geneticsandhealth.com

KQED Public Broadcasting in San Francisco recently did a radio story about the UC San Francisco Canine Behavioral Genetics Project run in collaboration with the University of Pennsylvania. The aims of the project are:

1. To explore the relationship between genes and behavior, both normal and abnormal, in domestic dogs.

2. To assess the amount and nature of genetic diversity in domestic dogs, both within and between breeds. 

Melanie Chang of the CBG project

Anyone wishing to send in their dog’s DNA can visit the site:

http://www.k9behavioralgenetics.com/ 

Dog DNA samples waiting to be processed at the CBG project 

However, it is often said dogs and their owners resemble each other. Now, researchers within this project are looking for those connections on a whole new level. They’re searching for the genes that cause common psychiatric problems in humans - by looking at the DNA of dogs. Have a listen to this very interesting broadcast:

http://www.kqed.org/quest/radio/view/836

Elaine Warburton  www.geneticsandhealth.com

G&H’s INTERVIEW WITH NAVIGENICS

Navigenics approached Genetics and Health for an interview. With so much written about similar genomics companies such as 23andme, Knome, deCODE genetics, I was intrigued to learn more about this company.  In particular, Navigenics appears to be the only company within this industry genre who provides a comprehensive wellness model – a healthcare model that Opaldia, the genetic screening and health surveillance company I founded, endorsed whole-heartedly. 

I interviewed Navigenics’ Medical Director Dr Michael A Nierenberg MD, clinical professor of medicine, emeritus at Stanford University to find out what makes Navigenics stand out amongst its competition.  He was most candid in his responses and the company has been open and transparent in responding to my follow-up queries, for which I am most grateful. 

The following article takes an in-depth look into Navigenics’ genomic services including how the company has positioned its services in relation to its ‘competition’ but importantly how Navigenics answers some of the ethical issues surrounding the whole field of genomic testing. The article has been divided into the following sections:

Navigenics #1 - ”My genes, my health, my life – who are Navigenics?”

Navigenics #2 - ”A stroll through your genomic park – about the test”

Navigenics #3 - ”SNP testing – can it be used for disease risk assessment?”

Navigenics #4 - ”Low penetrance v high pentrance genes”

Navigenics #5 - ”Corporate or pragmatic genomics”

Navigenics #6 - ”Privacy, insurance, GINA and ethics”

Navigenics #7 - ”The barriers to success!”

Navigenics #1 -  ”My genes, my health, my life – who are Navigenics? 

The much anticipated launch! 

April 8^th, 2008 Navigenics Inc launches its genomics service In New York. 

It has branded its service as “Navigenics Health Compass”.  

In its launch literature the company writes: “Navigenics aims to transform medicine from a ‘sick care’ model of ‘wait and see’ to the emergence of early risk detection.  It aims to empower individuals with opportunity and knowledge and to take preventative steps and a hands on approach to their family’s health and wellness” 

Navigenics – a veritable who’s who in genetics and business 

Navigenics has some highly influential supporters including Kleiner, Perkins, Caulfield and Byers (KP) and Sequoia Capital who have recently invested just under US$4m.   Amongst its heavy hitting Board members, co-founders and partners are David Brailer, until recently the Bush Administration’s point man on electronic health records and more recently Chairman of Health Evolution Partners, a private equity fund that invests in healthcare.   

Company co-founders are Dietrich Stephan, a Director at the Translational Genomics Research Institute and David Agus, a protein biomarker researcher at Cedars-Sinai Medical Hospital in LA.  Navigenics CEO Mari Baker was KPs ‘executive in residence’ and is former President of BabyCenter a website for parents. 

Also advising is politically connected Greg Simon, now President of Michael Milken’s FasterCures organization and previously Al Gore’s chief domestic policy advisor. 

Navigenics has close ties to Affymetrix and uses Affy’s gene chip (23andme uses Illumina’s chip).  Affy’s former associate general counsel Stephen Moore is now Navigenic’s general counsel and the company’s VP Business development, Sean George was also at Affy.  Amy duRoss, Navigenics Head of Policy and Business Affairs, was formerly with the Californian Institute of Regenerative Medicine and is also Navigenics’ spokeswoman.

Navigenics #2 - A stroll through your genomic park – about the test

The Navigenics service 

When you sign up to the Navigenics service you effectively enrol as a member and not as a patient or customer.   For US$2,500 you subscribe to an annual package which includes a genomic scan to identify your lifetime risk (compared to an average American male or female) of developing 18 core, treatable diseases such as heart disease, Alzheimer’s and type II diabetes.  Included in the package is on-line and telephone support from experienced genetic counselors who will hand-hold you throughout the process and be available to discuss your results in ‘easy to understand’ language.   

Over time, Navigenics will be adding additional information and tests to its core service portfolio.  As a subscriber to the service, you will have access and be advised of any updates and how they relate specifically to your health risk profile.  Ongoing annual subscription for the Navigenics service will be at a nominal annual subscription, currently US$250 pa. After subscribing you will receive a saliva collection kit.  Once you have provided a saliva sample you will be asked to send the kit back to Navigenics’ CLIA certified lab in California, where your DNA will be extracted and scanned. 

About a month later, you will be informed of your test results via your own personal account within a secure area of Navigenics’s website.  The results also come with an explanation of what they mean and the impact they may have on your overall health risk profile.  In addition there will be guidance and recommendations on how to mitigate against any identified health risk through your personalized health action plan. 

For example, if you are a female, your profile may contain the following results: 

Alzheimer’s              Yourself  8%            Average population   17%

Breast cancer          Yourself 14%           Average population   13% 

This is interpreted as you are at lower risk of developing Alzheimer’s during your life compared to the average female but at higher risk of developing breast cancer during your life than an average female.  Regular screening for breast abnormalities may well be a sound investment for your ongoing wellness.   Dr Nierenberg comments “Navigenics wishes to foster an ongoing partnership and relationship between members and the medical communities.  This is achieved through an educational program and repeated contact. The genetic screen only provides part of the health picture so our members need to be counseled on the fact that as there is also a large environmental component involved in disease development, so they may never get it.” Genetic counseling and having adequate access to this service is of paramount importance to Navigenics.  Elissa Levin, heads up the company’s genetic counseling services.  Dr Nierenberg describes the counseling team. “The counseling team provides members with clinically based knowledge to promote a greater understanding of their health risks, to decrease anxiety at every step of the way and to encourage them to take positive steps to live as long and healthy a life as possible.” 

Navigenics #3 - SNP testing – can it be used for disease risk assessment?

Navigenics has focused on around 100 of the most definitive research papers on SNPs (single nucleotide polymorphisms) that have been most strongly associated with 18 particular diseases such as breast cancer, type II diabetes, cardiovascular disease.  The company has built an algorithm (mathematical computer program) that estimates the risk of a healthy person developing a disease if their genome has the relevant SNP. 

The company has spent immense time and financial resources on engaging its panel of scientific and clinical experts to analyze the many hundreds of SNP association studies.  Says Dr Nierenberg:  

“It is a pre-requisite for Navigenics that any SNP to be included within its core panel must have undergone rigorous scientific and clinical evaluation and had the supporting research replicated in an appropriately peer reviewed paper. Functional data and magnitude of effect are also taken into account, but studies are not automatically excluded if functional data is unavailable or the effect estimate is small.  That being said, there is currently nothing on our panel with a relative risk less than 1.1 of developing a disease if the associated SNP is carried.”

99% of human DNA sequences are the same across the entire human population.  However, variations in DNA sequence can have a major impact on how humans respond to disease, the environment and drugs & medicines. SNPs are DNA sequences that occur when a single nucleotide (A,T,C or G) in the genome sequence is altered.  For example - AAGCT to ATGCT.  For a variation to be considered a SNP, it must occur in more than 1% of the population.  Many SNPs have no effect on cell function, but many could predispose people to disease or influence their response to a drug.     

A single altered gene is only part of the disease development equation.  To be more at risk of developing a complex disease such as cardiovascular disease, an individual needs to possess a number of interactive SNP ‘faults’ in multiple genes.    A SNP that is common in one geographical region or ethnic group, may be much rarer in another.  This is one of the main arguments against using SNP based analysis for the whole population.  For example if much of the research has been carried out on a predominantly ‘pure’ Caucasian cohort the test for that particular SNP may only be appropriate for a Caucasian and not, for example an African or Asian. Navigenics SNP data is largely Caucasian, but the company is more versant in the actual calculations of life-time risk and who was included in that which may well include non-Caucasians.  Dr Nierenberg explains:  

“We have reason to believe that the data applies across ethnic groups, but further data is needed to confirm this, will be collected over time, and reported to our members. For now we are very transparent about the groups in which the studies are done, whether Caucasian or in some cases non-Caucasians. Where associations have been looked for in other ethnic groups, generally we see that the effect sizes are consistent across other ethnicities including African Americans and Asians.”

As there are estimated to be over 3 million SNPs there is obviously an infinite amount of research still to be carried out on SNPs and their interaction both at the genomic and environmental levels.  The SNP single gene model is probably too simplistic to be able to provide risk scores for complex diseases, so I asked Dr Nierenberg how Navigenics foresaw their product evolving in the future. 

Dr Nierenberg advised: “We’re not basing our entire approach per se on the test, rather we’re looking at promoting wellness and the effects of the environment on health.  We believe our members should be pointed in the right direction in terms of their genetic predisposition to disease and offered suggestions on how to manage their risk.” 

In terms of the future evolution of the product, Dr Nierenberg advises that the results of ongoing studies will be added to the core test to enhance Navigenics’ service offering.

Navigenics #4 - Low penetrance v high pentrance genes

SNPs are known as ‘low penetrance genes’ where it will only sometimes produce the symptom or trait with which it has been associated at a detectable level. In this case of low penetrance it is difficult to distinguish environmental from genetic factors.   

Whereas ‘high penetrance genes’ such as the breast cancer genes BRCA 1 and 2 are those where the trait will almost always be shown by the individual carrying the faulty gene. In this case a BRCA 1 and 2 carrier will have over an 80% chance of developing breast and/or ovarian cancer in their lifetime. 

Most high penetrance genes have been patented, in the case of BRCA 1 and 2 by Myriad Inc. It is a costly process to obtain a license from the patent owner and in the case of BRCA 1 and 2 the cost of a Myriad test is around the US $5,000 mark, two to five times more expensive than genomic screens and therefore probably prohibitive to genomic screening companies, in cost terms.   

Dr Nierenberg advises that Navigenics have made a conscious decision not to include high penetrance genes in their core panel, preferring to focus on those low penetrance genes that are affected by environmental factors.  

“In the case of the BRCA genes, only a relatively small proportion of the population – as low as 5% - carry one or more of these genes.  We are focused on SNPs that are apparent within whole populations. We make it clear in our literature that we do not test for this type of gene.”

Navigenics #5 - Corporate or pragmatic genomics

Navigenics uses Affymetrix’s gene chip which is able to test around 1 million genetic markers.  However Navigenics has initially focused on 18 specific, treatable diseases which form the foundation of its designated SNP panel.  This panel will expand over time.   

I asked the question of what happened to a member’s DNA – whether it was disposed of or stored.  Dr Nierenberg explained that a member’s DNA was stored in anticipation of future advances in understanding how genes and the environment interact in disease development.  

“As part of a member’s subscription, we will automatically advise them of these advances if relevant to their particular disease risk as and when they become available”. 

The phrases “corporate genomics” and “the Microsoft of the genome” have been coined to describe the genomic business models of companies such as Navigenics, 23andMe and deCODE Genetics where getting access to your genome would require handing it over to a company that assumes it knows better that you do which parts of your genome you are entitled to see, and then charge you again and again for updated versions of the same product.  

However, the counter argument is that from modern medicine’s inception, we have effectively handed over our health to a specialist body – physicians, who themselves have grown into corporate organisations – hospitals, who, in turn are empowered to make clinical and financial judgements on our health and well-being.  Is there really a tangible difference? 

Dr Nierenberg defends Navigenics business model by citing the very arguments that are causing deep rifts within the genetics communities, namely, Navigenics only provides members with test results for diseases where firstly there is sufficient research on the SNPs in terms of robustness of testing, clinical utility and outcomes, and secondly, but importantly, the diseases they focus on are those where something can be done to reduce the risk of developing that disease - such as exercise, nutrition and regular screening.   

Imagine the confusion and furore if Navigenics were to provide its members with their full 1 million marker analysis!  Navigenics’ (and others) sensible, if somewhat patriarchal approach of ‘drip feeding’ results to members as and when the research is robust enough to bring the SNP into the public domain, is one that should be applauded not derided.  Yes, they and others have the potential to make substantial profits if consumers chose the service.  But the corporate world is also littered with the carcasses of companies that didn’t get it right.

Navigenics #6 - Privacy, insurance, GINA and ethics

One of the main consumer concerns is that of privacy of information, both in terms that a genetic test has been undertaken but also that the results of the test are kept private and out of the public domain.  At the time of writing, the controversial GINA (Genetic Information Non-discrimination Act) is being passed by the US Senate which will enable genetic testing information to be kept private and not be used to discriminate against an individual, particularly by the insurance industry.  The insurance industry is understandable against the Bill. 

Dr Nierenberg advises that Navigenics takes the whole issue of security of data very seriously.   

“Navigenics takes precautions such as multiple servers, encryption and security audits … each member has access to their own section of the website which is password protected.  However, if a member forgets their password, there is a highly complicated route to get back in.  It is not just a case of emailing the password to an email address. … GINA legislation will be helpful in terms of protecting sensitive information”. 

The company has also incorporated a rigorous Ethics Advisory Board tasked to develop policies and report to the Executive Board in the fields of bioethics, patient rights, health information technology and technology and data security. In terms of working with the health insurance industry, Dr Nierenberg advises that at present the service Navigenics offers is ‘direct to consumer’ and the health insurance industry are not be involved.  However the company is already working with health insurers to integrate this type of testing and service as part of a standard medical insurance package. He says: 

“There is a strong health economic argument to incorporate genomic screening into an insurance package.  Catching a disease early or even preventing it must surely be in everyone’s best interests rather than wait until the disease is established and expensive treatment is almost certainly needed”. Dr Nierenberg uses the example of HIV testing and the insurance industry to describe how he believes genetic testing will evolve over time   “… Back in the 1980’s HIV testing was hated and received a lot of abuse.  However, over time the test has become familiar and everyone is comfortable with routine HIV testing”. Dr Nierenberg says Navigenics is also looking to expand it results service to become fully consumer friendly.  They are working on communication with its members via cell phone and other internet options.  However none of these initiatives can be implemented until the company is satisfied that data can be securely anonymized. 

Navigenics, at some stage, may well request permission to use a member’s DNA in anonymized research studies.  This will bring up a wealth of ethical issues such as informed consent at every stage of the research and explanation for what research the DNA will be used for.

Navigenics #7 - The barriers to success!

When founding my old company Opaldia, probably the single most challenging aspect of early adoption of genetic testing was physician barriers.  Mostly this was borne out of a genuine lack of understanding about the field of genetics but also concerns that testing was too much in its infancy and tests had not been subject to rigorous clinical evaluation.  Time and again the phrase ‘not undergone prospective trials’ was used as a defense against bringing genetic testing into mainstream medical practice. 

I was interested to learn how Navigenics proposed to overcome this barrier.  Dr Nierenberg explained that Navigenics has developed a physician education program. He says: 

“We’re developing our own on-line material but we’re working with Medscape to develop a CME program for physicians to access.  The educational material will cover a large range of information from basic to complex”. 

Dr Nierenberg describes the word genetics as a ‘hot button’, guaranteed to evoke the strongest of reactions.  He is philosophical about the fact that genetics research and genetic advances are still at a relatively embryonic stage but made the analogy with the completeness of research into the effects of smoking. 

“Everyone is aware that smoking is not good for health. Would it be of benefit to continue smoking until all the research evidence to prove smoking is bad for you is complete?  … This is the same for genetics…. If there is a means to identify an individual’s increased risk of developing a disease then isn’t it is everyone’s best interests to use this?” 

There have been a number of recent articles on the state of play of personalized genomics, some of which have been less than complimentary to industry players.  The term ‘recreational genomics’ has been used to describe these services.  I asked Dr Nierenberg whether he considered any damage had been done to this embryonic field by these articles.  Dr Nierenberg again took a philosophical view on these articles:  “Navigenics is no way a ‘recreational’ genomics company and does not wish to contemplate entering any ‘recreational’ field. It is a company focusing on the wellness and prevention aspects of health.  Our service focuses on actionable entities and things of substance such as cardiac disease, not eye colour or such like. We welcome regulation and make heavy use of genetic counseling.  We follow all NHGC latest guidelines and best practice and more …” Dr Nierenberg and his team believe that the company is ‘… ahead of the curve and when you are leading a new field there is always a level of scepticism about your service and an expectation that you will be challenged every step of the way’. He cited the example of the C-Reactive Protein (CRP) test and its use in diagnosing cardiac inflammation.  Initially the test was ridiculed but now it is established as a routine diagnostic test used alongside CT heart scanning – another modality which initially received poor press.   

Navigenics firmly believes that through educating both clinicians and the public, it will only be a matter of time before genomic screening become part of routine health and wellness programs.  By focusing its services around a serious health delivery model rather than a ‘recreational’ model, Navigenics anticipates achieving its company vision to transform medicine from a ‘sick care’ model of ‘wait and see’ to the emergence of early risk detection and prevention of disease development.

I hope you enjoyed this series of articles about Navigenics’ Wellness Services.  I am most thankful to Dr Michael Nierenberg and the Navigenics’ team for the opportunity to discuss in-depth the issues surrounding the whole field of personal genomics services, wellness and health management.

Elaine Warburton  www.geneticsandhealth.com

Icelandic company deCode Genetics has announced it has signed a Letter of Intent to offer its genetic testing products to US Preventative Medicine customers.

US Preventative Medicine is a Dallas based company. The company has developed a suite of prevention, early detection and chronic condition management products and services that improve health outcomes while reducing health care costs.  It’s products are as follows:

“The signing of the letter of intent with DeCode is significant because we will be the first entity in the US and internationally to offer a full continuum of geographically dispersed, comprehensive solutions for personalized medicine,” Christopher Fey, chairman and CEO of US Preventive Medicine, said in a statement.

Elaine Warburton www.geneticsandhealth.com

As readers of Genetics and Health know, I am vocal in my support of providing patients with a wealth of education, information and advice before, during and after they undergo a genetic test.

With this in mind, Navigenics is a company I have had my eye on for some-while.  The company offers a comprehensive SNP based genetic risk assessment screen but has placed great emphasis on the ‘preventative health, wellness and ongoing support’ aspect for its customers and members.

Navigenics kindly agreed to be interviewed on all aspects of the company’s service, its philosophy and also provided comment on the various ethical and scientific debates that are currently raging around the whole subject of genetic testing.

Watch this space! ….

Elaine Warburton  www.geneticsandhealth.com

In January, The New England Journal of Medicine published an article criticizing the popularization of genetic testing by companies such as 23andme, deCode, Navigenics and Knome who doctors believe are introducing genetic testing prematurely into a commercial setting and confusing public and medics alike.  The authors of this article coined the phrase ‘recreational genomics’ for this type of testing.

While all of these companies claim that their tests should not be used as the basis for medical decisions, some physicians are concerned that customers for these tests will nevertheless begin seeking medical direction based on their results.  Doctors have been unprepared for the genetic advice they need to give their patients. 

The British Medical Journal has also published an equally critical article on the commercialization of genetic testing written by Exeter University Professor of Epidemiology and Public Health, David Melzer, whose own interest lies in research on genetic and conventional risk factors for chronic conditions of ageing.

Among the author’s concerns, is the need for strong regulatory oversight of genetic tests, tests based on empirical evidence, and public and physician education based on sound and transparent information.

“Although major scientific progress has been made, clinical applications are still mostly unclear,” Melzer wrote.

He suggests the key value of genetic markers may be in providing clues about disease mechanisms. On the other hand, he argues that few of the current markers are useful diagnostically, particularly those associated with moderately increased risk and/or with conditions for which no preventative interventions are available.

My personal belief is that introducing innovative genetic testing technology has to start somewhere.  With genetics we will never understand 100% of the complexities and interactions between our DNA and the environment - that is for the ‘divine being’ to know.  These genomic companies have taken a huge financial and clinical risk in bringing these tests to the market.  The tests are in their infancy and each of these companies are transparent in advising their customers of this fact.  That said, massive scientific research continues to take place to build on the knowledge base of these tests, so that they may be refined.  This process will never end.

Most people are fascinated by their own health and mortality.  Millions are spent on a plethora of mainly unproven herbal drugs and vitamins that have the potential to damage an individual. Many more millions are spent on early stage gadget technology.  If an individual wishes to understand more about their genetic risk of developing a disease and testing is available then it is also their right to purchase a test.  Surely commonsense dictates that raising an individual’s awareness of their risk of developing a disease is a good thing, particularly if that individual takes control of their health and well-being by perhaps eating more sensibly and taking more exercise?

In terms of patient education and support, these genomic companies are providing some pretty in-depth advice which customers have access to.  In terms of doctors providing more information and education on genetic testing, the question needs to be asked as to why medical schools are not preparing doctors sufficiently in this area? Genetics and the knowledge of the role it will play in diagnostics has been around for a good 30 years! Genetics and genetic testing should be part of the core medical training syllabus and ongoing professional education. 

… and for that matter it also needs to be taught as part of the school syllabus.  Genetics has come along way since Gregor Mendel’s pea plant experiments in the 1850’s and yet that is still the level of subject knowledge our kids are being taught!

Elaine Warburton  www.geneticsandhealth.com

Peripheral artery disease image showing ‘furring up’ of arteries 

Peripheral vascular disease (PVD) can affect the arteries, the veins or the lymph vessels. The most common and important type of PVD is peripheral artery disease, which affects about 8 million Americans.  It becomes more common as a person gets older, and by age 65, about 12 to 20 % of the population has it. Diagnosis is critical, as people with peripheral artery disease have a four to five times higher risk of heart attack or stroke. 

Peripheral Artery Disease (PAD) results from fatty deposits (plaque) that build up in the arteries outside the heart (peripheral arteries); mainly the arteries supplying the legs and feet. This buildup narrows or blocks a person’s arteries and reduces the amount of blood and oxygen delivered to their leg muscles and feet. The iliac, femoral, popliteal and tibial arteries are commonly affected.  the main symptoms are leg pain that won’t go away when exercising;  foot or toe wounds that won’t heal quickly, lower temperature in the affected leg and at worst gangrene.

Researchers from Duke University Medical Center, funded by NIH took two strains of mice with surgically-induced blocked blood flow that mimicked human response to PAD. One strain recovered well, showing restored blood flow and little tissue death; the other had greater tissue loss and poor recovery of normal blood flow. On further investigation, the scientists isolated a small area on chromosome 7 which appeared to give protection from PAD.

Dr. Brian Annex, professor of medicine and director of vascular medicine at Duke, says the study stemmed directly from his clinical experience. “Over and over, I’d see two patients show up at the same time. They would be the same sex, same age, have identical risk factors and have similar blockages in their arteries. One of them would experience very slow progression of the disease, while the other would face limb loss or death within six months. I just knew there just had to be a genetic basis for it.”

“Essentially, we now have a field of about 20 genes that we think may be involved in shaping the way peripheral artery disease develops,” says Annex. “At this point, we are not certain which ones are playing an active role, however. Still, we feel strongly that our discovery opens a new wave of investigation that may one day yield novel prevention strategies or treatments.”

Elaine Warburton www.geneticsandhealth.com