A Guide to Genetic Counseling

Wendy R. Uhlmann, Jane L. Schuette, Beverly M. Yashar, Wendy R. Uhlmann, Jane L. Schuette, Beverly Yashar

• Publisher: Wiley-Blackwell
• Year: 2011
• ISBN:
  9781118210536
• Edition: 2
• Topic: Medicine
• Subtopic: Genetics in Medicine

The first book devoted exclusively to the principles and practice of genetic counseling—now in a new edition

First published in 1998, A Guide to Genetic Counseling quickly became a bestselling and widely recognized text, used nationally and internationally in genetic counseling training programs. Now in its eagerly anticipated Second Edition, it provides a thoroughly revised and comprehensive overview of genetic counseling, focusing on the components, theoretical framework, and unique approach to patient care that are the basis of this profession. The book defines the core competencies and covers the genetic counseling process from case initiation to completion—in addition to addressing global professional issues—with an emphasis on describing fundamental principles and practices.

Chapters are written by leaders in the field of genetic counseling and are organized to facilitate academic instruction and skill attainment. They provide the most up-to-date coverage of:

• The history and practice of genetic counseling
  
  

• Family history
  
  

• Interviewing
  
  

• Case preparation and management
  
  

• Psychosocial counseling
  
  

• Patient education
  
  

• Risk communication and decision-making
  
  

• Medical genetics evaluation
  
  

• Understanding genetic testing
  
  

• Medical documentation
  
  

• Multicultural counseling
  
  

• Ethical and legal issues
  
  

• Student supervision
  
  

• Genetic counseling research
  
  

• Professional development
  
  

• Genetics education and outreach
  
  

• Evolving roles and expanding opportunities
  
  

• Case examples
  
  

A Guide to Genetic Counseling, Second Edition belongs on the syllabi of all medical and human genetics and genetic counseling training programs. It is an indispensable reference for both students and healthcare professionals working with patients who have or are at risk for genetic conditions.

1

The Practice of Genetic Counseling

Ann P. Walker, M.A., C.G.C.

THE PRACTICE OF GENETIC COUNSELING

Historical Overview

Until the beginning of the last century there existed little scientifically based information for those concerned about the chances of an apparently familial disorder or birth defect occurring (or recurring) in themselves or their off spring. Observations of such conditions had sometimes led to correct interpretations of their pattern of inheritance, as in the understanding of hemophilia evidenced by the Talmudic proscription against circumcising brothers of bleeders, in Broca’s report of a seemingly dominant breast cancer predisposition in five generations of his wife’s family (Broca, 1866), or in societal taboos against marriages between close relatives. Often, however, birth defects and familial disorders were attributed to exogenous causes—punishment (or perhaps, favor) by a deity, a misdeed on the part of the parents (usually the mother), a fright, a curse, or some natural phenomenon such as an eclipse. Indeed, similar beliefs are still widespread in many cultures and may even figure subliminally in irrational fears of people who are otherwise quite scientifically and medically sophisticated.

Throughout the late 1700s and the 1800s, investigators wrestled with how traits might be transmitted. Lamarck’s theories regarding the inheritance of acquired characteristics persisted into the twentieth century. Darwin recognized that characteristics that were advantageous in particular circumstances might increase the likelihood of survival and reproduction—eventually generating a population sufficiently different from its ancestors as to constitute a new species. Darwin’s cousin Galton, by studying families and twin pairs, attempted to develop mathematical models to tease out the relative contributions of environment and heredity. By the start of the twentieth century, Bateson and Garrod had each recognized that the familial occurrence of alcaptonuria (described by Garrod in 1899) and other recessive “inborn errors of metabolism” could be explained by the neglected and recently rediscovered laws of Mendel (Garrod, 1902). Thus began a new era in which the pattern of inheritance of certain genetic conditions—and hence their risks of recurrence—could be deduced, providing a more scientific basis for genetic counseling.

During the last century, understanding of genetic disorders, variability, mechanisms, and contributions to common diseases grew exponentially. Medical technology exploded, leading to a host of new genetic testing capabilities, including prenatal and ultimately preimplantation genetic diagnosis. Less dramatic but equally important advances occurred in the study of human behavior, in public health policy, in ethics, and in counseling theory. Concomitantly, people began to assume greater responsibility for their own health care decisions. The activity of genetic counseling developed and changed accordingly over this period. It is only since the 1970s, however, that a profession specifically devoted to genetic counseling has arisen. The education and practice of these professionals encompasses all of the above elements, enabling them, as members of genetics health care teams, to bridge such diverse disciplines as research scientist, clinical geneticist, primary health care provider, social worker, and hospital administrator. More importantly, today’s genetic counselor provides a service that is unique—distinct from the contributions of these other individuals—for patients and families who seek to understand and cope with both the genetic and the psychosocial aspects of disorders they confront.

Less than 40 years after the first master’s degrees were awarded in genetic counseling, these new professionals have achieved a prominent place in genetic health care delivery, education, and public policy development. They have formed professional organizations in several countries, been involved in starting training programs, developed mechanisms for accrediting over 30 North American genetic counseling graduate programs, and become board certified, credentialed, registered, and/or licensed as distinct health professionals. This chapter gives an overview of these developments—and perhaps also a glimpse of the challenges and excitement to come.

Models of Genetic Counseling

Eugenic Model Sheldon Reed is credited with introducing the term “genetic counseling” in 1947 (Reed, 1955). However, the practice of advising people about inherited traits had actually begun about 1906, shortly after Bateson suggested that the new medical and biological study of heredity be called “genetics.” By then the public (and many scientists) had been intrigued by the thought that this new science might be able to identify hereditary factors contributing not only to medical diseases, including mental retardation, but also to social and behavioral diseases such as poverty, crime, and mental illness. Galton himself had suggested in 1885 that “eugenics” (a word he coined from the Greek ευγενηζ, meaning “well-born”) become the study of “agencies under social control that may improve or impair racial qualities of future generations, either physically or mentally” (Carr-Saunders, 1929).

Enthusiasm over the possibility that genetics might be used to improve the human condition gave rise, for example, to the Eugenics Records Office at Cold Springs Harbor (a section of the Carnegie Institution of Washington’s Department of Genetics) and establishment of a chair of eugenics (by bequest of Galton himself) at University College London. Not only did scientists in these institutions collect data on human traits, they also sometimes provided information to affected families— usually with the intention of persuading them not to reproduce. Unfortunately, at least at the Eugenics Records Office, data collection was often scientifically unsound, or was biased and tainted by social or political agendas. The eugenics movement, initially well-intentioned, ultimately had disastrous consequences. By 1926, 23 of the 48 United States had laws mandating sterilization of the “mentally defective” and over 6000 people had been sterilized (most involuntarily) (Carr-Saunders, 1929). Astoundingly, this practice persisted up into the 1960s and 1970s in some countries (Wooldridge, 1997). In 1924 the U.S. passed the Immigration Restriction Act, instituting quotas to limit immigration by various “inferior” ethnic groups. In Germany, euthanasia for the “genetically defective” was legalized in 1939—leading to the deaths of over 70,000 people with hereditary disorders in addition to Jews, Romanies (gypsies) and others killed in the holocaust (Neel, 1994). Revulsion at the specter of these past abuses in the name of mandatory eugenics is at the heart of the “nondirective” approach to genetic counseling that prevails today.¹

Medical/Preventive Model Distress at the outcomes of what had started out as legitimate scientific inquiry caused most geneticists to retreat from advising families about potentially hereditary conditions for at least a decade. However, by the mid-1940s, heredity clinics had been started at the Universities of Michigan and Minnesota and at the Hospital for Sick Children in London (Harper, 2004). A decade later, during a time when prevention had become a new focus of medicine, several additional genetics clinics were established. Information about risks was offered—based almost entirely on empirical observations—so that families could avoid recurrences of disorders that had already occurred. However in 1956, few diagnostic tests were available. Knowledge of the physical structure of DNA was only three years old; there was no way to prospectively identify unaffected carriers of genetic conditions; and given that it was still thought that there were 48 chromosomes in the human genome and that our mechanism of sex determination was the same as in Drosophila (Therman, 1993; Miller and Therman, 2001), the basis for chromosomal syndromes was completely unknown. Even with the goal of preventing genetic disorders, there was little for genetic counseling to offer families but information, sympathy, and the option to avoid childbearing. Many geneticists assumed that “rational” families would want to do so (Resta, 1997).

Decision-Making Model The capabilities of genetics changed dramatically over the next 10 years as the correct human diploid complement of 46 was reported by Tjio and Levan (1956) and the cytogenetics of Down (Lejeune et al., 1959), Klinefelter (Jacobs and Strong, 1959), and Turner (Ford et al., 1959) syndromes and trisomies 13 (Patau et al., 1960) and 18 (Edwards et al., 1960; Patau et al., 1960; Smith et al., 1960) were elucidated. Over this decade it also became possible to identify carriers for a- or p-thalassemia (Kunkel et al., 1957; Weatherall, 1963), a host of abnormal hemoglobins, and metabolic diseases such as galactosemia (Hsia, 1958), Tay–Sachs disease (Volk et al., 1964), and G6PD deficiency (Childs, 1958), among others. Amniocentesis was first utilized for prenatal diagnosis—initially for sex determination by Barr body analysis (Serr et al., 1955)—and then for karyotyping (Steele and Breg, 1966). In 1967, the first diagnosis of a fetal chromosome anomaly was reported (Jacobson and Barter, 1967).

These advances in genetics meant that families had some new options to better assess their risks and possibly avoid a genetic disorder. However, the choices were by no means straightforward. Tests were not always informative. Prenatal diagnosis was novel, and its potential pitfalls were incompletely understood. Explaining the technologies and the choices was time-consuming. However, clinical genetics’ tenet of nondirective counseling was beginning to be echoed elsewhere as medicine began to shift from its traditional, paternalistic approach toward promoting patient autonomy in decision-making. The emphasis in genetic counseling shifted too, from simply providing information that families would presumably use to make “rational” decisions (thereby preventing genetic disorders) toward a more interactive process in which individuals were not only educated about risks but also helped with the difficult tasks of exploring issues related to the disorder in question, and of making decisions about reproduction, testing, or management that were consistent with their own needs and values.

Psychotherapeutic Model Although families often come to genetic counseling seeking information, they cannot really process or act on it effectively without dealing with the powerful reactions this information can evoke. For this reason, exploring with clients their experiences, emotional responses, goals, cultural and religious beliefs, financial and social resources, family and interpersonal dynamics, and coping styles has become an integral part of the genetic counseling process. Genetic disorders and birth defects often catch individuals completely off-guard—raising anxiety about the unfamiliar, assaulting the self-image, provoking fears for one’s own future and that of other family members, and generating guilt. Even a client who brings a lifetime of experience with a disorder, or who has known about his or her own or reproductive risk for some time, will have cognitive or emotional “baggage” that may need to be addressed for counseling to succeed. A skilled genetic counselor must be able to elicit and recognize these factors, distinguish appropriate from pathological responses, reassure clients (when appropriate) that their reactions are normal, prepare them for new issues and emotions that may loom ahead, and help them marshal intrinsic and extrinsic resources to promote coping and adjustment. A few genetic counselors have chosen to develop these skills to a higher degree by obtaining additional training so that they can provide longer-term therapy for dysfunctional families or for individuals whose underlying psychopathology complicates genetic counseling.

DEFINITION AND GOALS OF GENETIC COUNSELING

1975 ASHG Definition of Genetic Counseling

In the early 1970s a committee of the American Society of Human Genetics (ASHG) proposed a definition of genetic counseling that was adopted by the Society in 1975. Though oft cited, no textbook of genetic counseling would be complete without it:

Genetic counseling is a communication process which deals with the human problems associated with the occurrence or risk of occurrence of a genetic disorder in a family. This process involves an attempt by one or more appropriately trained persons to help the individual or family to: (1) comprehend the medical facts including the diagnosis, probable course of the disorder, and the available management, (2) appreciate the way heredity contributes to the disorder and the risk of recurrence in specified relatives, (3) understand the alternatives for dealing with the risk of recurrence, (4) choose a course of action which seems to them appropriate in their view of their risk, their family goals, and their ethical and religious standards and act in accordance with that decision, and (5) to make the best possible adjustment to the disorder in an affected family member and/or to the risk of recurrence of that disorder.

—American Society of Human Genetics, 1975

This definition held up quite well for a time, articulating as it does several central features of genetic counseling. The first is the two-way nature of the interaction— quite different from the “advice-giving” of the eugenics period or the primarily information-based counseling characteristic of the mid-twentieth century. The second is that genetic counseling is a process, ideally taking place over a period of time so the client can gradually assimilate complex or distressing information regarding diagnosis, prognosis, and risk and formulate decisions or strategies. The third is the emphasis on the client’s autonomy in decision-making related to reproduction, testing, or treatment, and the recognition that such decisions will appropriately be different depending on the personal, family, and cultural contexts in which they are made. The fourth acknowledges that the occurrence or risk for a genetic disorder can have a family-wide impact differ...