The process of a psychiatric genetic counseling is dynamic. The components outlined below do not necessarily occur in a linear manner. Components of a genetic counseling session fall into two broad categories: information gathering and information provision (content) and support.
Information gathering
Needs identification. Individuals seek genetic counseling for many reasons. Although providing information on recurrence risks (the risks to relatives of developing the condition) is often regarded as the primary purpose of the intervention, many individuals are fearful and apprehensive about receiving such information, and patients may not wish to hear it. Rather, many patients simply seek an explanation for why the illness developed (
11 ). In addition, some "unaffected" relatives seek psychiatric genetic counseling out of fear that they may be experiencing emerging psychiatric symptoms. In this situation, involvement of a psychiatrist is essential. Also, in genetic counseling with an affected individual, it is important for the counselor to establish that the individual is currently well enough to be an active participant in the session. If this is not the case, the counselor should discuss the possibility of rescheduling for a time when the individual might be better able to take the most from the session.
Identifying the disease construct. Patients and families invariably devise a construct to explain the occurrence of an illness, particularly in the face of uncertainty. Often these explanations invoke feelings of guilt, and the genetic counseling session is arguably one of the best forums for addressing these issues (
12 ). Furthermore, without exploration and incorporation of the existing construct into the explanation of the disease, little new understanding is taken away from genetic counseling (
13 ).
Family history. It is important to obtain a family history relatively early in the session. However, this task is best begun once rapport has been established, which will facilitate openness to questions. Questions address, but are not limited to, the following areas: medications, hospitalizations, birth defects, learning difficulties, substance abuse, and reasons for the deaths of family members. The resulting pedigree has multiple uses. First, it can provide information about medical conditions in the family, such as breast cancer, which allows referrals to be discussed and made as appropriate. Second, it can be used to gather information that may indicate the presence of a genetic syndrome underlying the mental illness (
14,
15,
16,
17,
18,
19 ). For example, it may indicate 22q11.2 deletion syndrome, or 22qDS. Approximately 25% of individuals with 22qDS develop a psychotic disorder, and the condition is estimated to affect up to 2% of individuals with schizophrenia (
20,
21 ); it is also likely to be underdiagnosed (
20 ). Evidence of a genetic syndrome may indicate referral to a medical genetics program for complete assessment.
Third, the pedigree can be used as an aid to explanations. Fourth, it can help in risk assessment. Factors influencing risk include the number of affected individuals in a family, their relationships to the individual of concern, and specific psychiatric diagnoses. Thus, whenever possible, diagnoses within the family should be confirmed by seeking consent and requesting medical reports and by involving a psychiatrist. In early psychosis a specific diagnosis may be unclear for a considerable time, and although risk assessment is possible for family members of individuals who have recently developed psychosis, the provision of accurate figures is to some degree diagnosis dependent. Thus the counselor should explain that a more specific risk assessment may be possible once the disorder has been more clearly defined diagnostically.
Information provision and support
Etiology. The bulk of a genetic counseling session involves a discussion with the patient about the importance of contributions of both genetic and environmental vulnerability factors in disease pathogenesis. Discussion of only one of these contributors not only may be overly simplistic but also may lead to undesired consequences, such as increased stigma (
5,
22,
23 ). The counselor should take care to explain in lay language, using pictorial aids when possible, current knowledge about the pathogenesis of the disorder, ongoing research that will help clarify pathogenesis further, issues surrounding the potential for genetic testing for psychiatric disorders in the future, and why testing is not currently clinically available.
Research demonstrates that observed patterns of inheritance of serious mental illnesses are best described by theoretical models involving interactions of about three different genes with the environment (
24 ). Many researchers now agree, however, that a quantitative trait model can probably be applied to psychotic disorders, in that when a certain number of genetic vulnerabilities have accumulated, the likelihood of developing the illness becomes very high. It seems likely that there is a large group of genes of which numerous smaller subgroups can interact together and with the environment to substantially increase an individual's vulnerability to serious mental illness. Thus different affected individuals may have different combinations of predisposing factors. Several recently identified genes have even been deemed worthy of the label "schizophrenia genes" (
25 ).
However, the picture is far from complete. For example, each of the genes identified confers only a modest degree of vulnerability to mental illness, with risk associated with the presence of a genetic variation approximately double the risk in the general population (about 2% compared with about 1%). Furthermore, it is not known how the interaction of different genes influences vulnerability, and because of the significant role of the environment, no genetic test will be able to absolutely predict who will and who will not develop the illness. These caveats effectively negate any current clinical relevance of testing for these genes. Also, even though these genes have been identified, the specific genetic mutations responsible for pathogenesis remain elusive, and the significance and mechanism of these genes in conferring susceptibility remain to be established (
25,
26 ). Furthermore, although there is now a small handful of genes that appear to confer increased vulnerability to schizophrenia, it seems likely that many more genes that also have this capacity have not yet been identified.
The existing disease construct is incorporated into the discussion of what is known about the etiology of serious mental illness, and misconceptions are clarified. The counselor should take special care to explore the individual's conceptualization of seriousness and chronicity of the illness in light of the information he or she is provided about etiology so that any feelings of fatalism or hopelessness can be addressed. The counselor can refer to the family history, and if the illness is present, the individual's feelings about it should be explored. A full discussion of environmental vulnerability factors often leads to questions about various life events—the individual may ask whether he or she, or others, could have contributed to the vulnerability. Again, exploration of emotions surrounding these issues is critical. It is important to discuss feelings about the lack of certainty in the information provided, because much remains unknown.
Recurrence risks. As noted above, recurrence risks are a source of much anxiety for many families affected by serious mental illness. Before providing estimates of risk, the counselor should carefully explore whether the patient wants to know about recurrence risks. If possible, the counselor should attempt to ascertain the patient's perception of risk before providing estimates of risk. Risks are usually provided in the form of ranges. The information must be accompanied by appropriate provisos, including the limitations of recurrence risk estimates based on empirical data and diagnostic uncertainty. The counselor should use different techniques to convey concepts of chance and risk—for example, by providing an estimate of the chance that an individual will be affected as well as an estimate that the individual will not be affected or by using percentages along with information about chances, presented as "1 in X chance." It is important to take time to discuss the impact of this information on the patient.
Decision-making support. In some scenarios, patients may have decisions to make—for example, about treatment and medication in preparation for or during pregnancy. In this situation, the counselor's role is to facilitate and support decision making, not to direct decisions, and to help the patient to adjust to his or her decisions.