Pharmacogenetic tests

Robertson JA. Consent and privacy in pharmacogenetic testing. Nature Genet 2001 28 207-209. 

IV. Why Are Most Pharmacogenetic Tests of Limited Clinical Utility ... 

The low predictive values of pharmacogenetic tests for most polymorphic variants means there will be false positive (when PPV is low) and false negative (when NPV is low) test results. Both reduce the clinical utility of the tests. There are a number of reasons for the reduced predictive values. 

As the PPV and NPV of pharmacogenetic tests approach 100% they become more useful, but this ideal is seldom approached with tests for common polymorphisms and haplotypes. In those cases, will predictive pharmacogenetic testing help physicians decide on treatment If there are no other drugs with lower risks or a greater margin of safety, they may have no choice but to administer the drug and monitor the patient closely. The nature of the... 

In light of the low predictive values of many pharmacogenetic tests, two other situations in which pharmacogenetic testing has been heralded need closer inspection their use in drug development and as a substitute for prescribing on an ethnic-racial basis. 

Since Congress gave it authority to regulate in vitro diagnostic tests in 1976, the FDA has included assessment of clinical validity based on data made available by the test s developer (Holtzman, 2000). In view of the paucity of published data on predictive values of pharmacogenetic tests, and the likelihood that many of them will be low (Table 9.2), data on clinical validity should be required before pharmacogenetic tests are used clinically.12... 

VII. Do Genetic Tests for Predicting Risk of Disease Require More Regulation than Pharmacogenetic Tests ... 

FDA clears Third Wave pharmacogenetic test. Pharmacogenomics. 6, 671-672. 

Fargher EA, Tricker K, Newman B, EUiott R, Roberts SA, Shaffer JL, Payne K. Current use of pharmacogenetic testing a national survey of thiopurine methyltrans-ferase (TPMT) testing prior to azathioprine prescription. J Clin Pharm Ther 2007 32 187-95. 

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