Gene testing has several limitations.
For example, some disorders that “run in families” can be traced to shared environmental exposures rather than any inherited susceptibility. In addition, some mutations detected by a positive test may never lead to disease. Furthermore, because existing tests look only for the more common mutations in a gene, some disease-causing mutations may escape detection.
Perhaps the most serious limitation of gene testing is that test information is not matched by state-of-the-art diagnostics and therapies.
To receive positive test results when there is no adequate treatment can be tragic.
Although gene testing poses little physical risk--usually no more than giving a blood sample--it can seriously affect a person’s life.
A test confirming the risk of a serious disease can trigger profound psychological consequences.
Because gene tests reveal information not only about the individual, but about his/her relatives and future offspring, the results can challenge family and other personal relationships.
With whom should a person share test results? Do the other family members want to know?
Because gene test results hold a wealth of information, confidentiality is a major concern.
Deciding to have a gene test is difficult.
In 1994, a poll asked people if they would take a test to predict diseases that might occur later in their lives; they were not told whether or not treatment or preventive measures would be available. About the same number of people said “no” as said “yes.”
The decision to undergo testing is a very personal one, and experts stress that it should be totally voluntary.
After receiving genetic counseling, a person should agree to the test only if she or he wants the information, not to accommodate relatives, health care providers, or anyone else. An important consideration to weigh is this: If the results are positive, are there available methods for state-of-the-art early detection? prevention? treatment?
Genetic counselors have a vital role to play.
These specially trained health professionals are skilled at supporting individuals when testing is being considered, when test results are received, and during the weeks and months afterward.
Since gene tests are designed to identify persons who have inherited a gene mutation, the first candidates for study will be members of high-risk families.
Later, tests may be offered to persons whose family history is less telling. Some day it may be possible to test a single blood sample for a whole range of gene mutations.
Before gene tests become generally available, specialists and society at large must come to grips with major technical, ethical, and economic concerns.
If widespread gene testing becomes a reality, it will be necessary to develop tests that are simple, cost-effective, and accurate. Testing thousands to millions of people will require many new labs and personnel as well as more genetic counselors. And widespread gene testing will require that many health care providers have a basic understanding of genetic principles in order to interpret the tests.
Date: 2015-12-24; view: 678