Genetic Testing And Counseling Research Paper

1. Genetic Counseling

1.1 The Role Of Genetic Counselors

Members of families with inherited disease often ask not only why the condition occurred, but also why it happened to them. They seek an opportunity to find personal meaning in the senseless nature of it, and search for ways to live with the risk of future disease (Kessler 1979). In this sense, many of the psychological issues associated with inherited diseases are not unique. However, the shared, familial nature of genetic risk raises additional issues that are distinctive. Inherited risk implies that what is a health risk to one individual may also be a risk to their biological relatives. In addition, when a client seeks information about inherited patterns of disease risk, it may have unanticipated consequences. Information previously kept private (such as nonpaternity or adoption) may be revealed, producing enduring effects on family relationships. Yet there also may be potential harms from failing to disclose genetic information. Individuals who remain uninformed of their risk of a preventable disease, such as advanced-stage colorectal cancer, may suffer needless morbidity or mortality.

Because of their training and expertise, genetic counselors are uniquely positioned to assess and explain the genetic nature of a disease and to address its implications. The process aims to be therapeutic in exploring with clients their feelings of guilt, shame, fatalism, or social isolation. Genetic counseling requires health care practitioners with expertise in medical genetics, knowledge of the disease for which the individual is at risk, effective communication skills, and short-term therapeutic counseling skills.

1.2 Genetic Counseling As A Profession

Until recently, genetic counseling focused primarily on risks for and consequences of rare conditions. Consequently, there are few genetic counseling providers worldwide. Also, because most of the evidence concerning the inherited causes of many diseases is relatively new, the practice of genetic counseling is only about 50 years old (Resta 1997). The short history of the field is reflected in the limited, but growing empirical evidence concerning the process of genetic counseling and its effectiveness in facilitating informed decision making and psychological adjustment.

The type of training received by genetic counseling providers is diverse, and thus it is likely that practices vary accordingly (Biesecker and Marteau 1999). In the United Kingdom and Australasia, genetic nurses often work alongside medical geneticists to provide genetic counseling services. In the USA, Canada, South Africa and increasingly, in the UK, genetic counselors receive specialized training at the master’s level to provide genetic counseling. In the vast majority of European and South American countries, medical geneticists or social workers provide genetic counseling. Genetic counseling services are not universally available, as underdeveloped nations usually have no specialized genetics health care providers.

1.3 The Principle Of Nondirectiveness

Nondirectiveness is often presented as a guiding ethical principle of genetic counseling due to the importance of personal autonomy in reproductive decision-making. Genetic information even outside the prenatal setting often has implications for future childbearing decisions. The principle of nondirectiveness is intended to suggest that within genetic counseling, patients are not persuaded or coerced into specific reproductive outcomes. However, there exists disagreement in the profession about the meaning of nondirectiveness and its importance in practice (Kessler 1997). An international survey of genetic providers revealed that nondirectiveness is a nearly universal guiding ethical principle in the majority of countries that offer prenatal genetic testing (Wertz et al. 1990). An exception is China, where providers are more inclined to advise their pregnant patients to terminate affected pregnancies in the interest of reducing the incidence of children affected with genetic conditions (Mao and Wertz 1997).

2. Genetic Testing

Genetic testing describes any test for inherited factors that may influence one’s health or the health of one’s relatives. The method of performing a genetic test ranges from DNA sequencing or direct mutation detection, to chromosomal analysis and protein function testing. In addition, the circumstances in which a genetic test may be done vary substantially. Therefore the genetics education and counseling that surround decisions about testing or implications of test results differ in content and emphasis.

2.1 Diagnostic Testing

Genetic tests have most often been used to diagnose genetic conditions. This has been done in three different ways. First, a genetic test may be used when a child or an adult is suspected to be affected with a certain condition based on the clinical features and pattern of inheritance. Second, newborn screening for a subset of rare largely treatable recessive genetic conditions has been conducted in the USA and most other developed counties for several decades. Third, prenatal genetic testing has been available since the early 1970s, used most often to diagnose Down syndrome and other chromosomal trisomies in the developing fetus.

The diagnostic tests used in a pediatric or adult medical genetics clinic are most often considered a part of good medical management when relatives (typically parents) or their health care providers are seeking to make a diagnosis. Genetics education and counseling typically addresses the genetic and medical implications of the diagnosis, as well as the psychological impact on the family of having to live with an affected family member, and the increased risk to other relatives.

Genetic counseling occurs infrequently in conjunction with newborn screening unless a diagnosis is made in an infant. When a genetic diagnosis is made, the parents usually require extensive education about medical management as well as recurrence risks. Although most of the conditions tested for are treatable (unlike the vast majority of single-gene conditions), they require exhaustive efforts by parents to keep their child on a specially restricted diet to ensure his her health.

Prenatal genetic testing is most often preceded by genetic counseling due to the highly personal nature of reproductive decision making. In most countries where prenatal testing is available, it is offered as an option to pregnant women who are at increased risk of having an affected child. Most commonly, this concerns those over the age of 35 years. Prenatal genetic counseling addresses the personal values of the client or couple, as they are guided in the exploration of the potential consequences of adverse test results. This includes envisioning both what their lives might be like if they had an affected child, or how they would feel subsequent to terminating a desired pregnancy.

2.2 Predictive Testing

Genetic testing is also used to predict genetic risk. Carrier testing, for example, is used to identify those who carry a gene mutation that does not affect them directly, but may place their children at risk. Relatives of individuals affected with certain genetic conditions and members of certain populations (e.g., Ashkenazi Jews) known to be at increased risk for certain conditions, are frequently offered carrier screening. Most carrier screening programs are accompanied by pretest genetics education, since it is important that those found to be carriers do not misinterpret the test result as indicating they have the disease.

Presymptomatic genetic testing is used to predict certain risk to an individual. Presymptomatic testing for Huntington’s disease, a degenerative neurological disorder, is one example. It is now possible for those at increased risk for Huntington’s disease to undergo presymptomatic testing prior to the onset of clinical symptoms. Inevitably, those found to carry a gene mutation develop the disease, for which there is no treatment. Due to the dire nature of these circumstances, the counseling that proceeds such testing is often extensive. Before presymptomatic testing was available, the majority of individuals at increased risk of developing Huntington’s disease reported that they would choose to undergo testing if it was developed. However, once testing was available, only a small minority of those at increased risk chose to go forward with testing.

The newest type of predictive genetic testing, predisposition or susceptibility testing, results in a risk estimate about one’s own future health. The first predisposition tests developed assess inherited susceptibility for cancer. An increased risk for at least two different types of colon cancer and breast and ovarian cancer can now be determined in members of hereditary cancer families. There are also populations of individuals more likely to carry susceptibility mutations due to shared heritage.

Susceptibility tests are being developed for many other common diseases and will be offered to an increasingly large portion of the population of developed nations. As demand for these tests increases, alternatives to in-person genetic counseling for pretest education will need to be developed and evaluated. Computer and Internet-based resources are likely to grow in their importance as sources of genetics information. These technologies allow information to be tailored to the characteristics of the individual user, allowing genetic counselors to focus on counseling and decision making rather than education and information delivery.

Initial studies of cancer susceptibility testing suggest that the majority of people express high levels of interest, but that many members of high-risk families do not utilize testing once it is offered (Croyle and Lerman 1999). The exploration of the psychological and behavioral costs and benefits of this type of testing have only just begun. Although individuals found to be noncarriers of cancer gene mutations report an alleviation of distress after testing, many mutation carriers do not engage in health behaviors that would allow the early detection of disease. These observations suggest that social and behavioral scientists will continue to play a key role in identifying ways to translate the achievements of genetics and biotechnology into improvements in public health.

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