Pre-conceptual genetic testing for multiple conditions

9 February 2010

The Times newspaper has reported that a new pre-conceptual genetic test that detects mutations associated with more than one hundred recessive conditions will shortly be launched in the UK via a fertility centre that offers in vitro fertilisation (IVF) and prenatal genetic diagnosis (PGD) procedures.

Already available direct-to-consumers in the US via the internet, the self-styled  ‘Universal Genetic Test’ uses a saliva sample to screen for mutations associated with a wide range of diseases and conditions – some very severe, others very minor. The idea is that one or both prospective parents can have the test (in some cases paid for by medical insurance) to determine if they are carriers; if carrier status for a particular condition or conditions is detected, then couples may opt for IVF with PGD to detect and remove embryos that would be affected (or be carriers for) the disease, or alternatively opt for prenatal diagnosis and termination of affected pregnancies, in either case avoiding the birth of a child with the condition.

Whilst pre-conceptual screening to prevent the birth of children affected by serious genetic diseases is a potentially very valuable measure, this new test raises a number of issues of concern. In particular, it is difficult for prospective users of the combined test to assess its potential utility. The numbers and nature of the mutations screened for in each of the conditions is not clear, so the value and accuracy of testing is difficult to gauge. Moreover, since the test covers a spectrum of conditions, which vary both in severity and in the availability of potential treatments, it is difficult to make a robust assessment of the implied risks and benefits of proceeding with testing for each condition.

Like other providers of genetic tests that are available via the internet, on a direct-to-consumer basis - Counsyl should ensure transparency by providing robust evidence of clinical and scientific validity in order to justify the clinical (and personal) utility of the test to both the consumer and the health professional who may offer the test.

Given that some consumers within the UK may initially seek to access this service via the internet, rather than via a clinic, the requirements of the Human Genetic Commission's common framework of principles for the governance of direct-to-consumer tests, which is currently being finalised, may well become relevant.

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