February 28, 2006 Features

Ethical Issues in Genetics Related to Hearing Loss

Recent technological advances in genetics have enabled the identification and characterization of dozens of genes involved in normal hearing. This knowledge has resulted in many new clinical applications for clients with hearing loss.

To ensure appropriate diagnosis and habilitation of people with genetic forms of hearing loss, audiologists and speech-language pathologists must work closely with clinical geneticists and genetic counselors. In addition to a basic understanding of genetic factors that cause hearing loss, it is important for speech and hearing professionals to understand the unique ethical challenges that new technologies in genetics may introduce.

Historical Factors

When reviewing current ethical issues, it is important to understand historical events related to the discovery of the genetic factors involved in causing hearing loss and the treatment of people who are deaf.

In the early 19th century, before Gregor Mendel completed his classic experiments to uncover the principles of inheritance, the causal relationship between heredity and human disorders such as deafness was neither suspected nor understood. In the mid-1800s, William Wilde, an otologist from Dublin, was the first to notice the occurrence of common surnames and the increased frequency of consanguinity among parents of children with hearing loss. This led him to postulate that hearing loss could somehow be transmitted through families; however, he thought that only congenital deafness was transmitted in this manner. By the 1880s, the idea that deafness could be inherited was more widely accepted, even though there was still no scientific understanding of the principles of human heredity.

It was around this time that the eugenics movement began to gain strength in the United States and it remained prominent through the 1930s. Eugenics is the concept that undesirable human traits can be eliminated and desirable traits made more prominent through selective breeding of only individuals who are considered to be genetically "fit." As eugenics relates to deaf and hard of hearing people, there were two schools of thought. "Negative eugenicists" believed that invasive measures (i.e., sterilization or institutionalization) should be used to stop the transmission of "bad genes." "Positive eugenicists," such as Alexander Graham Bell, believed that oralism, elimination of deaf schools, and deaf/hearing marriages were appropriate measures to curb the growth of the deaf population.

The ultimate abuse of people with disabilities occurred in Nazi-controlled Germany, beginning in the 1930s and directly evolved from eugenics ideology. As a result of Hitler's government allowing scientists to explore the idea of racial cleansing, a law was passed to prevent "diseased offspring." This law, in addition to leading to the annihilation of thousands of citizens who were Jewish and disabled, also resulted in the murder of more than 1,600 people who were deaf. An additional 17,000 individuals who were deaf were sterilized or forced to have abortions.

The 1950s brought scientific advances, including the discovery of the structure of DNA, sparking a renewed interest in Mendel's classic experiments on genetic characteristics. The fundamental principles of heredity in humans began to be understood. Physicians discovered that certain human disorders were associated with specific changes in chromosome structure, and the field of modern human genetics was born.

There was a great desire among the human geneticists in the 1950s to distinguish modern genetics from the abuses that resulted from the eugenics movement of the late 1800s and early 1900s. Modern-day human geneticists have valued neutrality toward and autonomy in reproductive decision-making, recognized the impact that decisions based on genetic information can have on the entire family, and recognized the importance of the nondirective provision of information to families in the genetic counseling process.

Developments in Modern Genetics

With the development of many new technologies in molecular genetics and the increasing use of animal models, modern genetics has grown explosively in the last several decades. This has resulted in the identification and characterization of a number of genes responsible for different hereditary traits, including deafness.

Progress in this area was enhanced by the Human Genome Project (HGP), an international effort jointly supported by the National Institutes of Health and the U.S. Department of Energy. The HGP accomplished its goal of determining the DNA sequence of the entire human genome, as well as a number of other model organisms, and continues to examine the ethical, social, and legal implications of genetic research.

Using modern technologies, many made possible by the HGP, scientists are increasingly able to identify genes, understand their protein products, and develop tests to identify genetic changes that lead to disease and human variation. Possible uses of genetic tests include diagnostic testing to determine if a person has a genetic disorder, predictive testing to determine the probability that a person will develop a specific genetic disorder, carrier testing to determine if individuals are at risk for transmitting a genetic disorder to offspring, prenatal testing for genetic disorders before birth, and newborn screening to identify the presence of a genetic condition at birth. As availability of genetic testing increases, consumers will, in all probability, view the use of this information as routine.

Why is Genetic Information So Ethically Complex?

The ethical implications of genetic testing for hereditary conditions have been a focus in the genetics literature for some time. The rapid introduction of genetic tests into clinical practice has resulted in the need for health care providers, including audiologists and SLPs, to become more informed about genetics and the risks and benefits of genetic testing.

Concerns regarding the ethics of genetic testing center around issues of discrimination, access to genetic information, privacy, confidentiality, informed consent, and risks/benefits. Genetic testing can have many advantages, such as providing information that is useful in decision making, reducing uncertainty and anxiety about the future, and providing practical information for optimal health care and education. The risks associated with genetic testing are generally not physical but may be psychological, financial, and/or social. They can have an undesirable impact on family dynamics, lead to concerns about employment or insurance discrimination, and impose psychological burdens when the test results are uncertain or undesirable.

Given these issues, the informed consent process is crucial and must be emphasized. Potential risks and benefits should be explained in an objective manner. The family must understand that although genetic information has implications for the entire family, the information will not be shared without written permission. To protect people from genetic discrimination, many state and federal laws have been established, but additional legal protections are needed.

Another issue that confronts all professionals is that of confidentiality. Results of genetic testing do not just affect the individual but may have an impact on many or all extended family members. Often, the client or client's parents may be eager to share results with other family members. If not, unless there is a threat of actual harm, the professional is bound by confidentiality requirements and may not share information. The question "what is actual harm?" is much debated in the ethics community and cannot be answered definitively.

Ethics and the Deaf Community

Molecular genetic testing for a variety of disorders presents many ethical, social, and legal challenges. The availability of genetic testing for deafness has raised unique and important ethical issues that need to be addressed. Many of these ethical implications are unique to hereditary deafness because of the existence of a Deaf culture with its own language (American Sign Language in the United States) and beliefs.

About 90% of those who identify themselves as being culturally Deaf choose a deaf partner. Sometimes termed "assortative mating," this process is based on linguistic, social, and cultural similarities. Many deaf couples have no preference for either deaf or hearing children, but would welcome the birth of a deaf child to share their language and culture.

This concept may be difficult for people with normal hearing to understand, but is related to the view that deafness can define a cultural affiliation rather than a disability.

In 2002, The Washington Post Magazine published an article about a deaf couple who searched for a deaf sperm donor with a family history of deafness, so that they could increase their chances of having a child who was deaf. Since deafness is considered a reason for exclusion from traditional sperm banks, the couple approached a deaf friend from a multi-generational deaf family, who agreed to be the donor. In the article, the biological mother described wanting to have a deaf child so that she would be able to communicate with the child naturally via American Sign Language and feel comfortable participating in school activities and social events. Two children who are deaf, fathered by the same donor, were born to this couple.

This case sparked a heated debate among ethicists worldwide about the ethics of using genetic information for the selection of a child who is deaf. Some ethicists argued that this case presented no ethical issues since this couple had the right to procreate with whomever they wanted and did not use any genetic testing or other technologies to increase their chances of having a child who is deaf. Others condemned the couple for limiting their children's potential to function in the mainstream world. This case led to a broader discussion of the implications of genetic testing and parental choice in the Deaf community.

Recently, several studies of the attitudes of people who are deaf and hard of hearing parents of children who are deaf regarding genetic technologies have been completed. These studies involved surveys of attitudes toward diagnostic and prenatal genetic testing. While the studies demonstrated generally positive attitudes by all groups toward the use of genetic testing for the purpose of determining the cause of hearing loss, attitudes concerning the use of prenatal diagnosis of hearing loss tended to be cautious or negative. Several of the studies found that many hearing parents of children who are deaf would not terminate a pregnancy with a prenatal diagnosis of deafness, but would use the information to help guide educational planning and emotional adjustment.

Additional studies are needed to examine the effect that genetic testing for deafness has on actual behaviors and choices made by families. As techniques for prenatal diagnosis of deafness become more widely available, a better idea of the demand for these procedures will be identified.

Genetic Ethics for Hearing and Speech Professionals

Audiologists play an important role in the entire process of genetic evaluation and testing. They may be the first professionals to suggest testing, even before the physician. All audiologists should be aware of the availability of genetic testing and should consider making the referral for every client with congenital or early-onset hearing loss. A genetics referral may also be appropriate for those with a family history of delayed-onset hearing loss.

An appreciation of the ethical considerations of genetic testing will allow the audiologist to convey the benefits and risks in an objective manner. Since genetic evaluation and testing must often be accomplished in one or two sessions with the geneticist and/or genetic counselor, parents may not have time to process the meaning of the results and concepts presented to them. The role of the audiologist is to reinforce correct information and refer families for additional genetic counseling, as needed.

Primary care physicians and otolaryngologists may want to order genetic tests for hearing loss, but may not know how or where to make the referral. In these cases, the audiologist can act as a liaison between the physician and a genetic counselor or program. In addition, audiologists may seek additional training through ASHA or other continuing education programs in the area of genetics so that they may feel comfortable providing basic information or interpretation of results when no genetic counselor is available.

Audiologists, SLPs, and other interested professionals may obtain additional information about genetics and/or the Gallaudet University Genetics Program by visiting the Genetics at Gallaudet Web site.

Ruth S. Marin, is an audiologist with more than 15 years of clinical experience and a current audiology PhD student and intern in the Genetics Program at Gallaudet University. Contact her at ruth.marin@gallaudet.edu

Kathleen S. Arnos, is a medical geneticist who is the director of the Genetics Program and a professor of Biology at Gallaudet University. Contact her at  kathleen.arnos@gallaudet.edu.

cite as: Marin, R. S.  & Arnos, K. S. (2006, February 28). Ethical Issues in Genetics Related to Hearing Loss. The ASHA Leader.

Focus on Divisions

Special Interest Divisions that focus on audiology cover genetics and other research and professional issues related to diagnosis, prevention, and treatment of hearing loss. These Divisions offer affiliates the opportunity to earn CEUs through self-study of Division publications, exclusive e-mail lists and Web forums, and other benefits. Learn more about the four audiology Divisions.

References

Arnos, K. S. (2003). The implications of genetic testing for deafness. Ear and Hearing, 24(4), 324-331.

Mundy, L. (2002, March 31), A world of their own. The Washington Post Magazine, 22-43.

Robin, N. H., Smith, R. J. H., & Matthews, A. L. (2003). Genetic testing for deafness in clinical practice. Audiological Medicine, 1, 89-93.

Ruben, R. J., Van de Water, T. R., & Steel, K. P. (1991). Genetics of hearing impairment. Annals of the New York Academy of Sciences, 630, 1-321.

Van Cleve, J. V. (2004). Genetics, disability, and deafness. Washington, DC: Gallaudet University Press.



  

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