Published by Computachem Services

P.O Box 297.
Alstonville. 2477
NSW Australia

Phone:
61 2 66285138

A new science of Pharmacogenomics is emerging.
It involves tailoring a medication to an individual.
This is pharmacy business, so an awareness, and suitable training, should be programmed, targeting this new science for delivery as a cognitive service by consultant pharmacists.

The production of proteins within the body is controlled by a gene code, so SNP's create differences in the proteins produced.
These include the proteins responsible for transport mechanisms, drug receptors and metabolic activity.
Pharmacogenetic differences account for variances in response by individuals, to the same drug.

Test kits are entering the market place which identify for patients the probability of developing a specific disease.
Such kits will enable pharmacogenetic factors to be measured and individual patient response to a drug to be assessed.
Following a test a patient would be matched to a therapeutic agent and a dosage schedule.
The interpretation of diagnostic information would seem to be an ideal pharmacy specific role.

Industry is moving towards identifying up to 10,000 genes through "genome chips".
This type of chip can identify DNA from mouth scrapings, and it is proposed that pharmacists ought to be able to conduct such tests utilising this "laboratory on a chip" technology.
Chips that are able to identify proteins are also in development, but will not find their way to market for a some time, as the technology is currently not very advanced.

It is predicted by some observers that within five years, all new drugs will require a patient to be genetically tested before actually taking the drug.
This will enable precise targeting of a drug for a particular patient profile.
The consequences of this technology may mean:

* Having to manufacture variations of the same molecule.
* Higher drug costs.
* Manufacturer profits may decline.
* Negligence suits against doctors and pharmacists if genetic testing is not offered to patients at the point of prescribing.
* Demands by Health Insurers for copies of DNA tests and exclusion of insurance cover for patients with predisposition for certain diseases.

Debate on genetic testing is gathering momentum globally, with some experts wishing to limit who has access to tests, and to determine what controls should exist, to counsel patients if they have an adverse result.
Some raise the ethics of pharmacies (and others) selling genetic test kits, highlighting concerns that such testing has implications for other family members and future children..
The other side of the argument sees consumers resenting the so called "experts" for telling them that they shouldn't know everything about themselves.
Tests have been available via the Internet for some time now, and these tests have been promoted for DNA paternity testing, motherless paternity testing, sibling DNA testing, twin DNA testing and grandparent DNA testing. It appears that provided tests are witnessed by a solicitor, the results are admissible in a court of law. (Visit link http://www.ezdna.com ).

Reports are also being published regarding US women who have had risky and unnecessary fetal tests following genetic screening of themselves and their partners. Others have terminated healthy pregnancies after having received faulty test results due to laboratory incompetence and not following clinical guidelines.

However, testing for cystic fibrosis is likely to become the first of many routine tests.
If a pregnant woman and her partner both carry any of the mutations that can cause the disease, there is a one in four chance of the child being born with cystic fibrosis.
If a follow-up test on the fetus confirms that it has inherited two defective copies of the CF gene, then the child will be born with the disease.
A hard decision will follow such a result, as to whether termination of pregnancy will take place.

Government regulation of genetic testing is still catching up with the market place.
What would happen, for instance, if what happened to Pan Pharmaceuticals recently, was to occur in one or more major genetic Australian testing laboratories?
It does bear some thought.

Concerns relating to the cost of testing have also been raised.
For example, since 1989 when the CF gene was first discovered, researchers have discovered more than 900 distinct mutations, that can cause some or all of the symptoms of the disease.
Routine screening for every mutation would be costly and time-consuming, so most commercial test kits cover 25-35 of the most common mutations.
One common mutation is called 5T.
It is present in one in 20 people but only contributes to cystic fibrosis if there is a second and much rarer mutation called R117H in the same gene.
By itself, the 5T mutation does not cause life threatening illness, and the consensus is that there is no justification for carrying out risky testing procedures on pregnant women (amniocentesis or chorionic villi sampling), or the termination of pregnancy.
However, there have been US reports of over-servicing, unnecessary fetal testing and terminations due to faulty results.
There are no official US government figures for CF mutations since population screening began in October 2001, and no records of outcomes have been kept.

In my research I discovered that this publication had highlighted genetic testing, counseling and pharmacy opportunities nearly two years ago (Follow this link: http://www.computachem.com.au/enewsletter/ed23e.html )
Reports of genetic testing for hypertension were also published so you could try the search engine on the front index page for this edition, you will come up with some extra reading.
Interestingly, there is training available for anyone interested in becoming a genetic counselor (details if you follow the link above), which would be a useful adjunct to pharmacy qualifications, and possibly something that will eventually find its way into pharmacy courses at universities.

Therapeutic agents generally interact with "target" proteins (receptors, enzymes, ion channels).
Most targets remain undiscovered as yet. There are 400 known drug receptors, but it is anticipated that around 3000 will be discovered into the future.
So while existing drugs may have a limited profit potential for drug manufacturers, there is a whole new world opening up for those who engage in genuine research into genomics.

In the UK, planning is already under way in the "Pharmacy in the Future" project and processes are being put in place to monitor and evaluate developments from laboratory testing to counseling of patients.
The program for pharmacists is embedded in the NHS Plan, and focuses on patient care, the revolution in diagnosis, and the improved use of medicines.

On balance, there appears to be agreement in the UK that Pharmacogenomics offers the potential to target medications more effectively, improve patient outcomes, and reduce adverse side effects.
This is expected to translate into major savings for the UK National Health Service, and pharmacists are actively being encouraged to prepare themselves by upgrading skills and qualifications, and so take full advantage of the new opportunities.
Australia commonly follows UK activities undertaken by the NHS, and adapts to provide local solutions.
By thinking about these processes now, community pharmacists can begin to build a business case for pharmacist involvement. There may also be scope to form alliances with other disciplines, particularly nurses, who are already trained to take various samples from patients, for laboratory testing.
The potential seems endless!