Introduction to Genetic Testing

What is genetic testing?

Genetic testing refers to any testing procedure used to detect the presence or absence of, or a change in, a particular gene or chromosome.

There are a number of different circumstances under which genetic testing may be offered. For example, testing can be used to confirm whether a person has or is likely to develop a genetic disorder, or if he or she is at risk of passing a genetic condition onto their children.

When is genetic testing used?

Genetic testing is used for a number of different purposes. Tests are referred to differently accordingly to their purpose and context, however, the laboratory procedures used across the various tests are often exactly the same.

The main uses of genetic testing relevant to jewish genetic disorders are summarised below.

  • Diagnostic testing – generally used to help diagnose a genetic condition in a person who is already exhibiting symptoms suggestive of a particular disorder.
  • Carrier testing – used to test whether or not a person carries one copy of a disorder-causing gene. Carrier testing is offered to individuals who, though usually unaffected by a particular disorder themselves, are at risk of passing it on to their children given their family history or ethnicity.
  • Prenatal testing – used with pregnant women to determine whether or not the foetus is affected by, or at risk of being affected by, a genetic condition.
  • Predictive testing – used to identify the presence of a specific mutation for a genetic disorder in a person who does not have symptoms but is at risk of developing the disorder later in life.

More information about each of these tests can be accessed by clicking on the relevant tabs in the side menu bar.

What is genetic screening?

Often the terms ‘screening’ and ‘testing’ are used interchangeably, even though they are not the same. The following descriptions help to highlight the differences between the two processes.

  • Carrier screening is a process of systematically offering a carrier test to a whole population (or sub-population) of healthy people, for a gene mutation that is known to be common in that group. 
  • Carrier testing refers to the tests that an individual would have, which may form part of a population screening process.

More information about carrier screening and testing for Jewish genetic disorders, genetic counselling, and information for carriers can be accessed by clicking on the relevant side menu tabs. Throughout all the materials there are a number of links that can be clicked on to view further information and support.