What is Genetic Testing

Genetic testing is the analysis of an individual’s genetic make- up to test for mutations in people’s genes which may result in genetic disorders like Huntington’s disease. In Australia, genetic testing is available for people who are at an increased risk of being a carrier for a mutated gene (e.g. breast cancer) or test those at risk of having inherited a genetic condition such as HD. Genetic testing is also utilised to confirm diagnosis of medical conditions.

Whilst genetic testing can inform you on medically important information pertaining to your health, there are advantages, disadvantages and limitations of being tested (please see table below).

If you are considering genetic testing and would like further information please contact:

• Genetic Health Services Victoria
• Murdoch Children’s Research Institute
• Egenetics a Government initiative which offers a single online access point for human genetics resources and information in Australia

Genetic testing for HD

Predictive testing for HD has been available since 1993 and remains a highly personal decision. This test can detect whether an individual has the gene expansion that causes HD. A genetic test cannot be used alone to clinically diagnose an individual with HD, but can confirm a diagnosis should someone be expressing symptoms.

Participation in predictive testing is available to those 18yrs and over who can provide informed consen demonstrating understanding of the processes and the benefits and risks of such a test.Individuals are able to withdraw from testing at any stage of the predictive testing process.

Deciding to undergo predictive testing

Deciding to be tested for the expanded HD gene is a big decision to make, one not to be underestimated due to the life-changing impact it may have for yourself and your family. Many people who are at risk are often driven to consider testing when planning for the future particularly in relation to children.

Even amongst family members the reason behind being tested or preferring to continue with the ‘at risk’ status varies and it is not uncommon that conflicting perspectives are debated. It is important to remember that there is no right or wrong answer to the decision of being tested, but individual choice.

In Victoria, predictive testing is available through Genetic Health Services Victoria, which is located at the Royal Children's Hospital. Costs are covered by Medicare. Testing is generally only available to people aged 18 years and over. A predictive testing coordinator and specialist medical team ensure that the person wishing to take the test receives appropriate information and counselling.

Genetic Health Services Victoria email: This e-mail address is being protected from spambots. You need JavaScript enabled to view it or phone: (03) 8341 6201.

Planning a family

Knowing that you are "at risk" for HD may influence your family planning decisions. For many people, the fear and guilt of the possibility of passing on the defective gene to children is often enough to prevent people from starting a family. However with advances in medicine and technology, families now have the opportunity to have children who will not have the defective gene for HD and will not in adult life develop any symptoms. If you are considering starting a family and would like further information and support in relation to your options you may wish to speak to a genetic counsellor about some of your options.

In Vitro Fertilisation (IVF)

IVF with Pre-implantation genetic diagnosis (IVF PGD) is an option that is now available for people who would like to ensure that their children will not have the defective gene for HD. In this procedure embryos are screened for the defective gene and only those that do not have the faulty gene are implanted into the women’s uterus.

Like all decisions of such magnitude, accessing the most up to date information and speaking to those involved in this program may be beneficial when deciding if this is an option that you wish to consider.

For further information please contact either the Predictive Testing Program or the Melbourne or Monash IVF clinics. They will be able to provide more detailed information in relation to the processes and cost involved.

Prenatal testing

It is possible to determine if a foetus is carrying the gene for HD. The prenatal procedures currently available are Amniocentesis and Chorionic Villus Sampling (CVS). However these tests don’t occur prior to week 12 of pregnancy and can increase the risk of a miscarriage. It is advisable that parents are clear on their purpose for testing their foetus as decisions will need to be made about continuing with the pregnancy if the foetus is gene positive, and how as parents you will you will manage this information if you decide to precede with the pregnancy. Should this be the option you are considering it is recommended that you speak to your obstetrician who can refer you to the appropriate genetic counsellor.

Genetic Discrimination

As DNA testing increasingly identifies differences in the genetic makeup of individuals, it becomes possible to discriminate based on genetic information. Discrimination against an individual can come in many forms. Most well known are in relation to both health and life insurance with people being denied policies based on family history and their own at risk status.

While many Australians are concerned about how their gene status may affect their employment only in certain situations are employers able to lawfully discriminate in employing people and this does not include being at risk or having the defective gene for HD. Furthermore you are not required to tell your employer about your gene results or condition unless it is relevant to your job and/or poses an occupational health and safety risk to yourself and others. The fear of potential discrimination and stigmatisation from insurance parties, employers, education institution as well as societal discrimination may lead some people not to undertake genetic tests at all.

Many instances of genetic discrimination are unlawful. In 2010 The University of Melbourne launched the Genetic Discrimination – Know Your Rights initiative which provides a website and booklet to provide Information on Genetic Discrimination in Victoria. If you are unsure if what you have experienced is genetic discrimination then the Genetic Discrimination- Know Your Rights is a good place to start for further information.