Choosing Wisely Australia has released its latest recommendations on the use of genetic testing, suggesting people avoid genetic tests for Alzheimer’s (APOE), coeliac disease and folate conversion (MTHFR).
Testing these genes is not recommended as results do not lead to improved health outcomes, and may create anxiety or false hope among patients.
Led by Australia’s health colleges, societies and associations and facilitated by NPS MedicineWise, the Choosing Wisely initiative drives conversations for the health care community and consumers about eliminating the use of unnecessary and sometimes harmful tests, treatments, and procedures.
Genetic testing as a health care tool
Genetic testing is currently available for more than 2,000 rare and common conditions. It is an important tool for the diagnosis of rare and inherited conditions such as cystic fibrosis. It can also guide health care and decisions for families with a strong history of cancer and high cholesterol.
However, its use it not always justified.
Genetic testing involves analysis of a person’s DNA: it looks for variants in genes that have an impact on our health. However many variants do not have a strong association with disease. Indeed, for many we don’t know what affect they have at all.
When the evidence for an association between a genetic variant and a health outcome is weak, genetic testing does not add any value for the health professional in making decisions about treatment and patient management. This reflects the fact that gene variants are common in our DNA and often not responsible for disease symptoms.
MTHFR and APOE are examples of genes with known and common variants that are poorly correlated with predicting future health risks.
Genetic testing to assess folate conversion
Folate and folic acid are forms of the vitamin B9. The MTHFR (5,10-methylenetetrahydrofolate reductase) gene is involved in converting the vitamin into a form the body can use.
There are two common variants in the MTHFR gene, and 60–70% of the general population will have at least one of these variants.
People with MTHFR variants still usually convert sufficient folate for the body to function as normal. With a good diet, the effects of a MTHFR variant can be easily overridden.
Low levels of folate are known to increase the risk of neural tube defects, where part of a baby’s brain or spinal cord does not form correctly during pregnancy. Australian women are advised to take folic acid for a minimum of one month before conception and for the first three months of pregnancy, irrespective of their MTHFR gene variant status.