Genetic counselling for schizophrenia

Evidence-Based Genetic Counseling for Psychiatric Disorders: A Road Map

Psychiatric disorders, such as schizophrenia, depression, anxiety, and bipolar disorder, are common conditions that arise as a result of complex and heterogeneous combinations of genetic and environmental factors. In contrast to childhood neurodevelopmental conditions such as autism and intellectual disability, there are no clinical practice guidelines for applying genetic testing in the context of these conditions. But genetic counseling and genetic testing are not synonymous, and people who live with psychiatric disorders and their family members are often interested in what psychiatric genetic counseling can offer. Further, research shows that it can improve outcomes like empowerment for this population. Despite this, psychiatric genetic counseling is not yet routinely or widely offered. This review describes the state of the evidence about the process and outcomes of psychiatric genetic counseling, focusing on its clinical implications and remaining research gaps.

Psychiatric genetic counseling: A mapping exercise

Psychiatric genetic counseling (PGC) is gradually developing globally, with countries in various stages of development. In some, PGC is established as a service or as part of research projects while in others, it is just emerging as a concept. In this article, we describe the current global landscape of this genetic counseling specialty and this field's professional development. Drawing on information provided by expert representatives from 16 countries, we highlight the following: (a) current understanding of PGC; (b) availability of services for patients; (c) availability of training; (d) healthcare system disparities and cultural differences impacting practice; and (e) anticipated challenges going forward.

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.

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.

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.

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.

Applications and limitations of empiric data in provision of recurrence risks for schizophrenia: a practical review for healthcare professionals providing clinical psychiatric genetics consultations

Schizophrenia is a common disorder that may frequently be encountered when taking family histories in the genetics clinic, whether or not the referral is for a psychiatric indication. Like in other common disorders, the provision of recurrence risks for schizophrenia is a complex clinical issue because empiric recurrence risks (while reasonably well established) can rarely be used without individual tailoring. This review seeks to identify and detail some pertinent issues surrounding the clinical utility of empiric recurrence risks for schizophrenia, and to provide an overview of important factors to consider when tailoring empiric risks for individual patients.

Genetic counselling for schizophrenia in the era of molecular genetics

OBJECTIVE

To review the role of genetic counselling for individuals with psychiatric illnesses.

METHOD

Using schizophrenia as an example and including updated information about a genetic subtype (22q deletion syndrome), we discuss the value of the genetic counselling process in psychiatry, with support from the literature and our clinical experience.

RESULTS

Genetic counselling, the process through which knowledge about the genetics of illnesses is shared, provides information on the inheritance of illnesses and their recurrence risks; addresses the concerns of patients, their families, and their health care providers; and supports patients and their families dealing with these illnesses. For comprehensive medical management, this service should be available to all individuals with schizophrenia and their families.

CONCLUSIONS

New findings in the genetics of psychiatric illness may have important clinical implications for patients and their families.

Towards a system of outcome indicators for mental health care

A system of outcome indicators for mental health care is urgently needed in order to ensure that clinicians, district health authorities, and directors of public health can monitor and evaluate mental health care. Theoretical aspects of health care indicators and the various classes of outcome measures available can be used to draw up a preliminary system of indicators of health care input, process and outcome for the major categories of mental illness, including schizophrenia, affective psychosis, neurosis, dementia, mental handicap, child psychiatry, forensic psychiatry, alcohol and drugs. Such a system is not intended to be definitive or exhaustive but rather to form a basis for development by clinicians, researchers and planners for their own requirements.

Psychiatry, molecular genetics and ethics: the new discoveries and the new issues

Recent developments in molecular genetics are examined with particular reference to psychiatry. The new technologies available have allowed significant advances in the understanding of certain illnesses such as familial Alzheimer's disease and Huntington's chorea, and will provide powerful tools to explore many other important psychiatric illnesses. The area of genetic counselling is already characterized by complex ethical issues. We can expect that as the new technologies provide the prospect of positive germ line genetic engineering, these ethical issues will become more complex. It is important that psychiatrists prepare themselves for these future developments and take an active role in leading the debate.