What is genetic testing?
Genetic testing examines DNA or proteins to identify anomalies linked to particular diseases, or to determine ancestry, paternity or ethnicity.
How is the testing done?
Genetic testing usually involves taking a biological sample which can be blood, cells or other body fluids and tissues. Typically a genetic test looks for changes in the DNA sequence which mean that a protein may not be produced in the right amount, or produced in a form that will not function, or is not produced at all.
Genomic testing looks at the whole genome (all genes and regions in between), exome sequencing and panels where more than five genes are evaluated simultaneously.
Targeted genetic testing looks for variations in specific genes. This can be done in a variety of ways including gene testing by genotyping, exome sequencing or microarray analysis.
Genetic screening includes genetic tests that are recommended to all members of a particular group (e.g., newborns, members of particular ethnic groups).
Why consider a genetic test?
Genetic testing can serve many purposes, but the results are not always easy to understand. Geneticists and genetic counsellors can help to interpret results and support decision making. Different types of genetic testing are carried out for different purposes.
Pre-symptomatic or predictive genetic testing is used to assess the risk of developing a
specific disease. This information can help to inform decisions around lifestyle and healthcare.