Genetic information and testing can relate to non-heritable conditions or heritable conditions.
Somatic testing refers to testing a specific tissue for variants occurring after birth and associated with disease of that tissue – can allow precise diagnosis, provide prognostic information, and perhaps lead to targeted treatment.
Germline testing is more focused on heritable conditions – revealing information on ‘shared genetic information’. “Positive” tests for variants do not necessarily mean that disease will arise. Testing is done on ‘normal’ tissue – blood, saliva, buccal swab etc.
Somatic genetic testing (e.g. analysis of a resected cancer specimen) can generally be treated the same as other testing – but germline testing which can reveal shared genetic information, or have reproductive implications, requires more specific consent and counselling.
Pre and post test counselling should be considered mandatory when undertaking pre-symptomatic or predictive genetic testing for a significant heritable disorder.
Genetic discrimination should be prohibited – but a fear of discrimination (e.g. by life insurance underwriters, or employers) may discourage people to undergo testing.
Direct to consumer tests are becoming more prevalent and may prevent appropriate pre and post test counselling.
| Pros | Cons | |
| · Prognostication
· Targeted treatments e.g. PARP inhibitors · Allow risk assessment of family members
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· Stress and anxiety, guilt
· Cost · Potential privacy and discrimination issues · Disclosure to family may provoke conflict
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