About Preventive Genomics

'Genomics' is the study of a person's genes and how it relates to their health and disease. Conventionally, genomic testing is predominantly used for diagnostic purposes in someone who already has symptoms. 'Preventive Genomics' is an innovative use of genomic testing, aiming to proactively identify hidden genetic risks in healthy adults, and address these genetic risks before symptoms develop, to prevent or delay the onset of illness for themselves, as well as to inform reproductive and genetic risks to their (future) children and other biological relatives. Once a genetic predisposition is identified, reproductive options may be considered by those at an increased reproductive risk. 

MGA provides a preventive genomics model of care similar to other renowned centres in the US (e.g. Massachusetts General Hospital, Brigham and Women’s Hospital, Boston), representing one of its kind in Australia and the Southern Hemisphere.

Genomic testing is done through a DNA sample via a cheek swab taken in the clinic. Discussions about the pros and cons of testing and what testing results may mean to a person, their (future) children, and the wider family, will take place prior to testing to help the person make an informed decision. DNA samples are then securely shipped to an appropriately accredited genomic laboratory for testing. 

The laboratory analyses genetic variants (genetic changes) in genes that are known to have an actionable impact. A genetic report is issued in approximately 3 months. 

The genetic reports are first reviewed by the MGA Clinical Geneticist for clinical interpretation and liaison with the laboratory for additional information if needed. Reports are then returned in a follow-up appointment by a genetics health professional who will discuss personal and familial implications ensuring all questions and concerns are answered/addressed. A detailed care plan, including any relevant risk management, is discussed with the person and returned to their general practitioner, with onward referrals made to relevant specialists if needed. 

The genes tested include those that predict major cardiac disorders (e.g. cardiomyopathy – anomalies of heart muscles/conduction), certain cancers (e.g. breast, ovarian, uterine, prostate, bowel), heritable diabetes, drug response (pharmacogenomics), and reproductive carrier risks. Testing can be customised based on each person's unique circumstance, stage of life, and personal/family history, and can range from comprehensive to tailored testing.

Generally only conditions with strong genetic predispositions, as well as those with available evidence-based and effective prevention, risk management and screening options, are included in the testing at the moment. In the future, testing for more common conditions with minor, non-heritable, genetic contributions (polygenic risk scores), such as coronary artery disease, type 1 or type 2 diabetes, late-onset cancers, may become available to guide personal health management with limited familial implications. 

Neurodegenerative disorders, such as early-onset dementia, are not included in preventive genomics testing, but can be considered in a diagnostic test in someone who already has symptoms.

Prevention is better than treatment. Research has shown that 1 in 75 people carries a heightened genetic risk for familial hypercholesterolaemia and certain cancers, that they had no prior knowledge or family history of.

Knowing about one’s underlying genetic predisposition allows a person to make informed decisions about their health, lifestyle choices, as well as life, career, and /or family planning. It may also have implications to the wider family.

Screening and early detection of symptoms associated with the identified genetic risk will also lead to better treatment outcomes, and may open up new/targeted treatment options, as well as other preventive opportunities (read How Genomics Supports Disease Prevention).   

Once a 'preventive genome' has been sequenced in a person, data are stored securely in the laboratory (can be released to the person upon request), and can be re-analysed in the future, for the following purposes:

• Diagnosis if other symptoms develop
• Precision treatment tailored to the specific genetic variants and molecular pathways
• Serving as a genomic legacy that may help provide genetic explanations for future generations