Recommendations for histocompatibility and immunogenetics

Choosing Wisely is a global initiative that seeks to encourage both doctors and patients to have a conversation about the value of treatments. The below recommendations for histocompatibility and immunogenetics are the result of a Choosing Wisely consultation involving the College.   

Evidence/guidance

• Approximately 0.8% of all genetic test requests received for germline mutations were unnecessary duplicate samples from patients who had already been successfully tested (Miller CE et al. Genetic counsellor review of genetic test orders in a reference laboratory reduces unnecessary testing. Am J Med Genet A 2014;164A:1094–1101).

• Adverse effects from venepuncture include vasovagal reactions, pain and bruising, and direct and indirect nerve damage (Stevenson M et al. Appendix 8 Diagnostic venepuncture: systematic review of adverse events. Health Technol Assess 2012;16:4; Kohn D, Bush A, Kessler I. Risk of venepuncture. Br Med J 1976;2:1133.

Patient information/decision aids

Genetic testing can help identify a disease risk or inherited condition. The results can help your doctor:

• decide which additional tests, if any, are required
• confirm a suspected diagnosis from previous tests undertaken
• choose ways to prevent or treat a condition.

Genetic testing may also tell you which family members are at risk.

However, sometimes a genetic test is not the best way to identify a disease risk or inherited condition. A routine blood test or procedure might be just as good. Therefore, it is important you discuss and understand the reasons for a genetic test with your doctor before agreeing to have a sample taken for testing.

Usually you don’t need to repeat a genetic test.

Your genetic information generally doesn’t change over your lifetime. Your doctor should check with you directly to confirm whether you have previously had the test. There is usually no reason to repeat a genetic test unless:

• your doctor thinks an error may have been made in the laboratory performing the test
• a new, more accurate test is available.