Genetic counseling for psychiatric disorders

Genetics of Eating Disorders: What the Clinician Needs to Know

Anorexia nervosa (AN), bulimia nervosa (BN), and binge-eating disorder (BED) are heritable conditions that are influenced by both genetic and environmental factors. Recent genome-wide association studies (GWAS) of AN have identified specific genetic loci implicated in AN, and genetic correlations have implicated both psychiatric and metabolic factors in its origin. No GWAS have been performed for BN or BED. Genetic counseling is an important tool and can aid families and patients in understanding risk for these illnesses.

Anticipating the Ethical Challenges of Psychiatric Genetic Testing

PURPOSE OF REVIEW

Genetic testing for mental illness is likely to become increasingly prevalent as the science behind it is refined. This article identifies anticipated ethical challenges for patients, psychiatrists, and genetic counselors and makes recommendations for addressing them.

RECENT FINDINGS

Many of the ethical challenges of psychiatric genetic testing are likely to stem from failures to comprehend the nature and implications of test results. Recent studies have identified gaps in the knowledge base of psychiatrists and genetic counselors, which limit their abilities to provide patients with appropriate education. A small number of studies have demonstrated the value of counseling in empowering patients to deal with relevant genetic information. Psychiatrists and other health professionals must be able to assist patients and families in making informed decisions about genetic testing and interpreting test results. Filling their knowledge gaps on these issues will be a critical step towards meeting these responsibilities.

Clinical applications of schizophrenia genetics: genetic diagnosis, risk, and counseling in the molecular era

Schizophrenia is a complex neuropsychiatric disease with documented clinical and genetic heterogeneity, and evidence for neurodevelopmental origins. Driven by new genetic technologies and advances in molecular medicine, there has recently been concrete progress in understanding some of the specific genetic causes of this serious psychiatric illness. In particular, several large rare structural variants have been convincingly associated with schizophrenia, in targeted studies over two decades with respect to 22q11.2 microdeletions, and more recently in large-scale, genome-wide case-control studies. These advances promise to help many families afflicted with this disease. In this review, we critically appraise recent developments in the field of schizophrenia genetics through the lens of immediate clinical applicability. Much work remains in translating the recent surge of genetic research discoveries into the clinic. The epidemiology and basic genetic parameters (such as penetrance and expression) of most genomic disorders associated with schizophrenia are not yet well characterized. To date, 22q11.2 deletion syndrome is the only established genetic subtype of schizophrenia of proven clinical relevance. We use this well-established association as a model to chart the pathway for translating emerging genetic discoveries into clinical practice. We also propose new directions for research involving general genetic risk prediction and counseling in schizophrenia.

Genetic Testing in Psychiatry: A Review of Attitudes and Beliefs

The advent of genetic testing for psychiatric conditions raises difficult questions about when and how the tests should be used. Development of policies regarding these issues may be informed in a variety of ways by the views of key stakeholders: patients, family members, healthcare professionals, and the general public. Here, we review empirical studies of attitudes towards genetic testing among these groups. Patients and family members show strong interest in diagnostic and predictive genetic testing, and to a considerable extent psychiatrists share their enthusiasm. Prenatal test utilization seems likely to depend both on parental views on abortion and the seriousness of the disorder. Parents show a surprising degree of interest in predictive testing of children, even when there are no preventive interventions available. Many persons report themselves ready to alter their lifestyles and plans for marriage and family in response to test results. Respondents also fear negative consequences, from discrimination to being unable to cope with knowledge of their "genetic fate." Empirical studies of beliefs about genetic testing suggest tests are likely to be embraced widely, but the studies have methodologic limitations, reducing the certainty of their conclusions, and indicating a need for further research with more representative samples.

Child and adolescent psychiatric genetics

The current status of child and adolescent psychiatric genetics appears promising in light of the initiation of genome-wide association studies (GWAS) for diverse polygenic disorders and the molecular elucidation of monogenic Rett syndrome, for which recent functional studies provide hope for pharmacological treatment strategies. Within the last 50 years, tremendous progress has been made in linking genetic variation to behavioral phenotypes and psychiatric disorders. We summarize the major findings of the Human Genome Project and dwell on largely unsuccessful candidate gene and linkage studies. GWAS for the first time offer the possibility to detect single nucleotide polymorphisms and copy number variants without a priori hypotheses as to their molecular etiology. At the same time it is becoming increasingly clear that very large sample sizes are required in order to enable genome wide significant findings, thus necessitating further large-scaled ascertainment schemes for the successful elucidation of the molecular genetics of childhood and adolescent psychiatric disorders. We conclude by reflecting on different scenarios for future research into the molecular basis of early onset psychiatric disorders. This review represents the introductory article of this special issue of the European Child and Adolescent Psychiatry.

Psychiatric genetic counselling for parents of individuals affected with psychotic disorders: a pilot study

AIM

There has been increasing interest in the concept of applying genetic counselling to psychiatric disorders, but despite its relevance to psychiatric illness, and interest from the target group, there have been no empiric investigations of psychiatric genetic counselling. In a population of unaffected parents of individuals with first episode as well as more chronic psychotic disorders, we aimed to investigate whether psychiatric genetic counselling: is perceived to be useful, could increase understanding of the causes of psychiatric illness and decrease concern about other relatives becoming affected.

METHODS

Subjects (n=13) participated in a genetic counselling session. The session was a clinical intervention similar to what would be carried out as part of a referral for any disease with a hereditary component, but specific for psychosis. Questionnaires were used to assess (pre-counselling): motivations for attending, concern about other relatives developing psychiatric illness, and (post-counselling) whether the intervention: (i) improved understanding of mental illness; (ii) modified concern about other relatives becoming affected; and (iii) was perceived to be useful.

RESULTS

Desire for knowledge motivated participation. Immediately after the session, and 1 month later >92% and 100% of participants, respectively, felt that the session was useful. Genetic counselling reduced concern about other relatives becoming affected as risks were lower than participants had expected. All participants felt that their understanding of the causes of psychiatric illness had improved through genetic counselling.

CONCLUSION

Psychiatric genetic counselling may benefit parents of individuals with psychiatric illnesses. Avenues for future research are highlighted.

Psychiatric genetic testing: attitudes and intentions among future users and providers

Psychiatric genetic research may eventually render possible psychiatric genetic testing. Whereas all genetic knowledge has certain characteristics raising ethical, legal, and social issues, psychiatric genetic knowledge adds more controversial issues. Ethical principles have been proposed as a guide in this field, but the optimal utilization of genetic testing has also been recognized to depend on knowledge of the potential consumers' attitudes. To provide knowledge to inform the public debate on mental illness and genetics, and the future conducting of psychiatric genetic testing and counseling, we surveyed attitudes toward psychiatric genetic testing among 397 patients with a psychiatric diagnosis, 164 of their relatives and 100 medical and psychology students. The results showed widespread interest in psychiatric genetic testing of self and child, but less support for prenatal testing. Psychiatric and somatic genetic testing attracted the same amounts of accept. General attitudes toward access to psychiatric genetic testing and information revealed substantial support for bioethical principles of autonomy and privacy. However, questions describing more specific situations revealed contradictions mirroring the bioethical dilemmas recognized in the field and variations in attitudes between groups with different levels of knowledge of genetics, different kinds of experience with mental illness, and different motives and preconceptions regarding psychiatric genetics. The contradictions and differences in attitudes among possible future users and providers of psychiatric genetic testing and counseling indicate ambivalence, insecurity, and perceived lack of knowledge in relation to psychiatric genetics. These results should inform further research and the future integration of psychiatric genetics into practice.

The importance of genetic counseling for individuals with schizophrenia and their relatives: potential clients' opinions and experiences

Genetic counseling is a health service, which has been indicated for individuals with psychiatric conditions in their families. However, little is known about the awareness and/or experiences of genetic counseling of this group. This study was designed to assess the awareness and perceptions of genetic counseling among individuals affected by schizophrenia and their relatives. Data was collected via two online surveys. Study participants either had schizophrenia or had a relative with schizophrenia and were recruited via links from schizophrenia web sites. This study was granted IRB approval. Sixty-eight individuals with schizophrenia and 145 relatives completed the surveys. Ninety-four percent of all respondents had not been offered genetic counseling. Zero percent of affected individuals and only 5% of relatives had received genetic counseling. Forty-four percent of affected individuals and 41% of relatives indicated that their family planning decisions were influenced by the presence of schizophrenia in their family. Seventy four percent of relatives and 72% of people with schizophrenia thought genetic counseling would be useful to them. Respondents indicated that they felt genetic counseling would be useful for them and that they would like to see a genetic counselor. However, few individuals are being offered genetic counseling services. The awareness of genetic counseling needs to be raised among physicians and families affected by schizophrenia.

Genetic counselling for psychiatric disorders

Family, adoption and twin studies demonstrate that many adult psychiatric disorders, including schizophrenia, major depression and bipolar disorder, have a clear genetic component. The aetiology of psychiatric disorders is a complex combination of both genetic and environmental components. While potential susceptibility genes for psychiatric disorders have been identified, interaction with the environment is a crucial component in disease development. Pharmacogenetics and genetic testing have the potential to play key roles in the future of clinical psychiatry. At present, an increased risk of psychiatric disorders can be identified through a detailed family history. The empirical risk of developing a disorder has been determined for many psychiatric disorders and can be used as a general guide. Genetic counselling can extend and enhance patient care by providing information to patients about the complexities of inheriting psychiatric disorders and the associated risks of recurrence. The genetic counselling process can facilitate informed decision making, alleviate misconceptions and reduce stigma through an improved understanding of the genetic cause of psychiatric disorders, and offer support to patients and their families.

A preliminary comparison of the hopes of researchers, clinicians, and families for the future ethical use of genetic findings on schizophrenia

A written questionnaire about genetic testing was distributed to all registrants at The 2004 World Congress of Psychiatric Genetics, mailed to clinical psychiatrists obtained from a directory of clinicians practicing in New York City, and mailed to members of families who have multiple affected family members with schizophrenia. A total of 274 individuals responded (162 researchers, 64 clinicians, and 48 family members). This survey shows that the majority of family members who completed the questionnaire (83.3%) would want to be tested if a genetic test were to become available. Over half of the family members (56.2%) would want prenatal testing. Similarly, over half of the clinicians (56.3%) would recommend it, despite only 25% of the researchers reporting that it would be a future useful tool. All of the clinicians surveyed thought adoption agencies should inform families about a family history of schizophrenia, while only half of the researchers thought this should be done (51.9%). These differences in opinions between consumers, their clinicians, and researchers could be based on a lack of understanding of the amount of risk conferred to family members by reported gene variants. Providing public discussions for placing these risks in perspective should be the responsibility of researchers. Open public discussion of the ethical and social uses of the information gained from psychiatric genetic research and its limitations is encouraged.

Emerging empirical evidence on the ethics of schizophrenia research

Many challenging ethical questions come with the scientific efforts to understand the nature and treatment of schizophrenia. The empirical study of ethical aspects of schizophrenia research has sought to clarify and resolve many of these questions. In this article we provide an overview of the existing data-based literature on schizophrenia research ethics and outline directions for future inquiry. We examine 5 broad categories of inquiry into the ethics of schizophrenia research: (1) Scientific designs (eg, placebo-controlled studies and medication-free intervals, prodromal and high-risk research, and genetics research); (2) informed consent and decision-making capacity, including assessment of decisional abilities, as well as intervention studies; (3) understanding and perceptions of risk and benefit (including the therapeutic misconception); (4) influences on research participation (including voluntarism, altruism, and other motivations); and (5) key participant safeguards, such as protocol review and participant advocates. We discuss how empirical work in each of these areas answers certain questions and raises new ones. Finally, we highlight important gaps in our understanding of ethically relevant aspects of schizophrenia research and offer a specific research agenda for empirical ethics.

Interest of adolescents in genetic testing for nicotine addiction susceptibility

OBJECTIVES

Genetic tests for nicotine addiction susceptibility may someday offer preventive medicine specialists new tools to reduce smoking among adolescents. This paper examines adolescents' interest in, and reasons behind interest in, such testing and correlates of interest.

METHODS

The sample included 211 healthy patients (ages 13-21) recruited from Georgetown University Medical Center's adolescent medicine clinic. Subjects completed a one-time behavioral survey immediately prior to or following a general medical check-up during calendar years 2001-2005. A 4-point self-report survey item served as the dependent variable.

RESULTS

Sixty-two percent of adolescents were interested in genetic testing. Among the 72% of adolescents who provided a reason for their interest, 35% would find the information interesting for general or nonspecific reasons, 30% would find it personally useful, 8% noted it would be irrelevant, and 13% stated it would be unimportant; school performance and interest in cancer susceptibility testing were associated with interest in nicotine addiction susceptibility testing (adjusted r2 = 21%; P < 0.0001).

CONCLUSIONS

Adolescent primary care patients will likely be receptive to comprehensive tobacco control programs incorporating genetic testing. Higher levels of educational achievement and greater interest in DNA-based preventive medicine may characterize those most interested. Offering testing will be contingent upon the development of safe and effective genetic tests.

The potential impact of genetic counseling for mental illness

Mental disorders are relatively highly heritable, yet complex with important interactions between genetic risk and environmental factors in determining illness expression. Due to the high prevalence of these complex disorders, steady increase in knowledge about genetic contributions, and increasing public awareness, this area may come to represent a significant proportion of all genetic counseling. The potential impact of genetic counseling in mental illness is broad. As well as the conventional expectations, genetic counseling may have the positive outcomes of reducing the guilt, shame, and stigma associated with mental illness, even within families. However, like many interventions in medicine, genetic counseling for mental disorders could potentially have unintended consequences resulting in increased stigma, guilt, and shame. The potential impacts of genetic education and providing recurrence risks on stigma are reviewed, as well as the role of education about the environment as a way of modifying family members' guilt. The review allows a preliminary formulation of a series of suggestions for genetic counseling in mental illness.

Family, twin, and adoption studies of bipolar disorder

Family, twin, and adoption studies have been essential in defining the genetic epidemiology of bipolar disorder over the past several decades. Family studies have documented that first-degree relatives of affected individuals have an excess risk of the disorder, while twin studies (and to a lesser extent, adoption studies) suggest that genes are largely responsible for this familial aggregation. We review these studies, including the magnitude of familial risk and heritability estimates, efforts to identify familial subtypes of bipolar disorder, and the implications of family/genetic data for validating nosologic boundaries. Taken together, these studies indicate that bipolar disorder is phenotypically and genetically complex.