Prenatal Diagnosis of Tay-Sachs Disease: A Case Study

A. INTRODUCTION

The subject of this case study is a couple, the Trosacks.  They are in their early to mid-40s and have been married for six years. They have been trying to become parents for two years. Rita Trosack is 43 years old, somewhat late for a first pregnancy, and in her first trimester; due in January. Ironically, because of the ages of the couple, their doctor, suggested screening for genetic defects by chorionic villus sampling (CVS). The Trosacks are both healthy, educated and have professional jobs, and both are excited about the pregnancy. While raised Catholics, neither is a practicing Catholic when Rita becomes pregnant. 

In July, the CVS indicates that the fetus has Tay-Sachs disease (also known as gangliosidosis), and the couple is referred to a clinic for high-risk perinatal counseling. Tay-Sachs disease is a fatal genetic disease causing the failure in an infant’s nervous system and rapid deterioration of the child’s body and mental capabilities. The disease usually has its onset at around six months and results in the death of a child by the age of 4 to 5. While appearing normal until six months of age, the child thereafter will begin to show diminished mental capacity and experience seizures, and by two years of age will likely be unable to crawl, turn over or sit, will have difficulty swallowing and breathing, and will become blind and paralyzed. There is no cure for this disease (NIH, 2011a). This case study will look at the care, counseling, and considerations given by the clinic nurse assigned as the Trosacks’ case manager. 

B. COMPOSITION OF AN INTERDISCIPLINARY TEAM, RATIONALE AND INFORMATION EXPECTED

In a case involving a fatal childhood genetic disease like Tay-Sachs, there are essential specialties to include in any interdisciplinary team for consultations, including a genetic counselor, mental health professional, a physician specializing in the treatment of Tay-Sachs, and related or similar diseases, a social worker, and a spiritual advisor.

Probably one of the key members must be a genetic counselor, who can explain both the origination of the disease based on the family history of both Rita and Peter Trosack, and the ramifications of having a child diagnosed prenatally with Tay-Sachs disease. Genetic counselors can answer questions about testing and test results, about conclusiveness or certainty of testing, and about further testing, as well as familial issues. In this case, the genetic counselor would explain the conclusiveness of the diagnosis, and the implications of proceeding with the birth.

Another important team member would be a mental health professional, such as a psychologist or psychiatrist with a specialty in dealing with death, dying, grieving and loss leading to depression, because the Trosacks, if they proceed with the birth will have to deal with the care and loss of their child, who will likely not survive past the age of four or five, with virtually no quality of life past the age of two. Both Rita and Peter blame themselves and possibly each other for the situation, and will need some counseling to deal with this, and their decision about the pregnancy, whatever they ultimately decide. They will be dealing with anger, at themselves and possibly each other, and mental health help and/or medication will assist in easing these feelings.

Another important team member, to help put the realities of the progress of the disease in perspective, and discuss treatment options would be a physician who is a specialist familiar with the prognosis, palliative treatment and outcome of the disease, to help the Trosacks understand the real medical nature of the disease and the care their child will need from six months old when the disease first manifests until his or her death at four to five years old. Medical specialists might also include a respiratory specialist, because Tay-Sachs babies develop respiratory issues usually after 6 months, and require constant attention during the child’s brief lifespan, a neurologist, given the relatively early devastation to the child’s nervous system, and a physician specializing in physical medicine and rehabilitation to help design a treatment plan to help the Trosacks child live as comfortably as possible, under the dire circumstances.

A social worker would also make a helpful member of the team assist in identifying for the Trosacks which state or federal agencies might help with care for them and their child, and what benefits are available for those with children suffering from Tay-Sachs or other fatal diseases requiring substantial care and assistance. Tay-Sachs is a disease which will require almost constant care of the Trosack’s baby once it is six-months-old, and social assistance and support groups will be critical in helping the Trosacks manage their difficult situation. The social worker can help point the Trosacks in the direction of the right support group, as discussed in more detail below, and these groups can be instrumental in helping parents get through the trying time dealing with the disease.

Also, even though the Trosacks say they don’t practice Catholicism now, given the Trosacks now professed strong religious and personal reasons for refusing abortion, a spiritual advisor or priest or expert would be helpful to offer whatever support might be available, such as prayer, fellowship, or even absolution in some form. If the couple persists in their decision, a spiritual advisor can help support their decision from a religious standpoint, and help them deal with questions raised by others from a spiritual point of view based on faith.

C. TEACHING PLAN FOR AN INITIAL CONSULTATION

A teaching plan for the Trosacks will not be easy to either prepare or deliver to the couple, due to the nature of the disease. Essentially prenatal genetic diagnosis of Tay-Sachs in a fetus is a death sentence to the unborn baby. The teaching plan must provide a wealth of technical medical information as well as options based on the two choices (keep or abort), sufficient to make an informed medical, personal, and ethical decision.

1. Genetic diagnosis

There are two kinds of genetic tests for Tay-Sachs, and three variations of the disease, infantile, juvenile, and chronic and adult-onset, affecting when the disease manifests, at 6 months of age, in childhood, or as an adult. (Mayo Clinic, 2011). The genetic tests both look at the Hex-A gene, which controls the buildup of lipids in cells, especially nerve cells in the brain. There is an enzyme assay, a biochemical test which determines the blood level of Hex-A (carriers have less of it), and there is DNA mutation analysis of the HEX-A gene. In this case, CVS was performed to screen for fetal genetic defects and confirmed Tay-Sachs in the fetus. Generally, CVS is performed in the vicinity of the 11th week of pregnancy to retrieve a sample of the placenta. Alternatively, amniocentesis can be performed somewhat later, around the 16th week, to retrieve amniotic fluid for testing. In this case, the earlier CVS screening was fortunate since it produced an earlier diagnosis, giving the Trosacks some additional time within which to decide which course to pursue. To assist with helping the couple accept the veracity of the diagnosis, they could undergo blood tests to confirm they are both Tay-Sachs carriers, as having confirmed the dire prognosis could help focus or crystalize the choices they have (NIH, 2011a). 

In the Trosacks’ case, the genetic counselor would need to explain to them the accuracy of the CVS testing, and probably would recommend blood tests for the parents to confirm the diagnosis. Of course, it is possible that the Trosacks may decide they do not wish to know the results of their own status as carriers, preferring instead to simply accept whatever happens in the ordinary course of their child’s term during pregnancy, and during the baby’s birth and life, short as it may be. 

Also, as part of educating the Trosacks about their predicament, the genetic counselor can explain how with current developments in genetic reproductive therapy, were the couple to decide to try again, it is possible to achieve in vitro fertilization with only healthy embryos which are free of the Tay-Sachs disease gene mutations, removing the risk of the baby developing the disease.

Also, a genetic counselor who can discuss family history and create a family genogram should spend some time educating the Trosacks about the familial and hereditary aspects of Tay-Sachs disease, and suggest to them that their relatives might consider testing when and if they consider having children.

2. Treatment

After the baby is born, the diagnosis of Tay-Sachs should be confirmed, by seeing an ophthalmologist who will look for the “cherry-red spot” behind the retina.  As there is no cure for Tay-Sachs disease at this time, treatment of a child diagnosed with the disease is mostly palliative and will be responsive to the typical symptoms as they arise (NIH, 2011b).

Generally, the first six months of the baby’s life is normal. Following that, degeneration of the nervous system begins, which will require treatment with anticonvulsants for seizures when they occur. Also, generally babies with Tay-Sachs disease eventually cannot swallow, and so treatment will include a nasogastric feeding tube to give the baby the requisite nutrition, adequate hydration as well, and various means to ensure the airway remains open.  An alternative is having an esophagogastronomy tube surgically inserted. Unable to crawl or walk or turn over, the child will require some physical therapy for atrophied muscles, which could delay complete loss of function for some limited time. Further degeneration includes blindness and deafness, and susceptibility to infection, most commonly the cause of death. Treatment will include measures to stimulate the child to make up for the loss of sight and sound, and to avoid infection, where possible, though it is a losing battle. 

3. Prognosis for Tay-Sachs

The prognosis for Tay-Sachs disease is dire despite medicine’s best efforts at this point. A child afflicted with the disease will die by the age of 4 to 5 years, likely from infection. The ordinary course of the disease results in the first six months of life being mostly normal, allowing for parents and child to spend time together before the disease hits. After that time, or in some cases earlier, the nerve cells, particularly in the brain, begin to deteriorate, and function becomes severely limited. The baby will have difficulty swallowing and breathing, and then will lose muscle control, and will cease being able to crawl or turn over, and then grow deaf and blind. The child will become susceptible to infections and will require constant attention and care. Currently, there are no drug trials, though genetic research is constantly being done. 

4. Support groups and referrals

There are support groups for Tay-Sachs disease sufferers and their families. The most prominent is the National Tay-Sachs and Allied Diseases Association (NTSAD) headquartered in Boston. This organization has an enormously broad range of information and services to assist families with dealing with this devastating disease. The people who manage the association are people who have lived through the nightmare of Tay-Sachs disease, and thus can offer both sympathy and real-world advice and assistance. It is a good place to start, and the Trosacks could be referred to this organization for information packets, and for helplines, such as Family Services, which can refer the Trosacks to local support groups and services.  

The National Organization of Rare Diseases (NORD) can be useful, but it is an organization that covers literally hundreds of diseases of which Tay-Sachs disease is only one. On the other hand, the NTSAD is focused on Tay-Sachs and its related diseases, and so offers a more insightful and specifically oriented array of information and options. 

Other groups that can offer help are the March of Dimes, a nationally recognized support organization for many difficult diseases, and also mdjunction.com, and geneticalliance.com.

Support groups are not just for the Tay-Sachs sufferer but for the families and caregivers for the patients. Giving them support is what helps them provide the very best care and love because they have that support.

5. Pregnancy information

In this case, the pregnancy itself is not high risk, aside from the mental anguish Rita Trosack may experience carrying a child she knows will die within a short time, and the effects that mental anguish might have on her physical condition and general health, such as eating well and taking care of her own health.  

Rita Trosack’s age does raise some significant issues for carrying the child full term to birth, and Rita must keep regular appointments with her obstetrician to monitor her condition and progress, keep regular ultrasound tests, and other traditional routine tests, such as for Down syndrome and gestational diabetes.  Some of the complications which might present during Rita Trosack’s pregnancy are hypertension, miscarriage, and placenta previa. She will also have to have a regular urinalysis to monitor sugar and urinary tract infections.

D. ETHICAL IMPLICATIONS OF PERSONAL GENETIC INFORMATION

1. Does personal genetic information afford society the opportunity to make choices people should ethically not have the chance to make?

Albert Einstein. Abraham Lincoln. John F. Kennedy. Stephen Hawking. Lou Gehrig.  Frederic Chopin. Woody Guthrie.  What do these people, arguably some of the most important in the past 150 years, have in common?  Each of them had or was suspected of having a genetic disease, to some varying degrees, affecting their quality of life. What parent, in a quest for the perfect child, would not consider averting a genetic defect for a healthy embryo? Should parents have the right to know their child’s personal genetic information before they are born in order to decide whether to have a child? This is possibly one of the most important ethical questions in our new millennium, where human beings have developed the power to control, to some extent, life itself. 

Yet where genetic information can be freely obtained, with detailed and comprehensive reports and explanations, any pregnancy becomes a potential chess match, where parents are pitted against chance, and science is the great equalizer. Ask a parent if they wish to start over, where an embryo or fetus is diagnosed with Addison’s Disease, an endocrine disorder. A genetic specialist might tell the parent that the baby will have Addison’s, explain the symptoms and prognosis, and those parents might decide to abort and try again within vitro fertilization of a genetically healthy embryo. However, what if the embryo is a future president of the United States? (Kennedy). How about an embryo with ALS (amyotrophic lateral sclerosis), a disease which notoriously cuts life short and causes debilitating symptoms? That would be one of the greatest baseball players of all time, who counted himself “the luckiest man on the face of the earth,” (Gehrig) and a physicist, one of the most brilliant minds in the world in recent memory (Hawking), married twice and the father of three children, developer of the string theory of quantum physics, and who has survived ALS for 50 years instead of the customary 10 years expected survival.

Some people might argue that while genetics provides the chance to avoid the most horrible outcomes (and Tay-Sachs disease might just be one of those horrendous outcomes), since we do not and cannot know the future with any certainty, the cavalier attitude of some people towards abortion as simply one method of filtering out unwanted defects or anomalies (and in some cultures, the sex of the child), changes the very nature of the randomness and chance of human birth and death, possibly affecting the history of mankind in ways we simply cannot even begin to understand or calculate. As proof, we can just imagine what humanity would have been like if any of the above lists of seven extraordinary people were aborted instead of born, nurtured and permitted to live out life, in most cases, to the fullest, and in some cases, despite their affliction or possibly as a direct result of it.

2. What ethical laws should be enacted regarding personal genetic information?

Life these days is getting closer to the science fiction of just thirty years ago. We have laws against cloning humans in most western democracies, but we know there are places where there are no such laws, and as science progresses, the chances for experimentation with such things are possible. Do we really want human clones? Of course, the issue within the issue of cloning is genetic engineering of clones, which is specifically including or excluding certain traits, and thus creating humans that fit certain requirements or specifications. Do we have the right to protect our personal genetic information to prevent someone from copying and using it to create a clone? Do we want to create a class of sports figures, suited for each particular sport? Do we want to create a class of laborers, engineered for strength and stamina, to build and construct, and to follow instructions obediently without complaint? Is that not slavery? 

We can change the question. Do we want to grow replacement organs that can be kept for us until needed? Hearts? Livers? Kidneys? Lungs?  What if these replacement organs must be grown in a cloned body that can be discarded when the organs are harvested? What if the bodies are not sentient? What if they are? If this sounds familiar, it should be, because it is the plot of the movie The Island. In-laws on file in half the states in America, some degree of stem cell research to develop the science to create replacement organs is permitted. It is just a few steps from there to The Island. Money has a way of overpowering ethics.

The United Nations does not agree on international law to prohibit cloning humans, but an advisory resolution was passed. For some countries, mainly mostly Catholic countries, there is strong opposition to cloning, abortion, or even genetics. But in other countries, the law is ambiguous and it appears there is a race to see who can be the first to clone a human if it hasn’t already been done.

It can be argued that there is a big difference between having genetic research done in order to determine whether a fetus has a dread disease, such as Tay-Sachs disease, and creating replacement organs or cloned humans.  But once the science is unleashed, it may be only a few short steps between these concepts of helping those in need because of disease and carrying out unethical specifications. In some countries, it is possible in the absence of law and with the ability to carry out genetic preferences, that perhaps no girls would be born, or not enough of them. Is this desirable? It is possible humanity might genetically engineer its own extinction.

3. Is there a right to privacy for personal genetic information? 

In this world of Twitter and Facebook, people have grown accustomed to people sharing almost any personal data, and many organizations require participation in this kind of a personal revelation because the more they know about you the more powerful they become.

Do we have a right to privacy concerning our genetic profile? What if we have a genetic profile that shows a defect that could lead to the onset of a genetic disease in the future? Would a life insurance company have the right to reject insurance or rate the premium higher because of that? Could health insurance be denied because of that? How about a job denied because of the risk of developing a genetic disorder in the future, either because it could have an impact on the employee’s performance or because of the insurance cost?

The more personal genetic information that becomes available, the more chances there are for that information to be used or abused, with choices made based on supposition or prognosis as opposed to fact and reality. 

For this reason, we may very well need some overall legal protection for the privacy of our genetic information to protect us from society jumping to conclusions about us based on genetic speculation. 

4. Ethical implications of using genetic information to prolong the life

Using genetics to give people afflicted with diseases a more normal life might not raise difficult ethical issues. However, as genetics is used to prolong human life by providing replacement organs, such as hearts, livers, lungs, kidneys, or other organs, and as humans are able to live beyond the traditional human life spans, perhaps to 150 or even 200 years, we may genetically compound the ability of humanity to coexist with our world. There are currently 7 billion people on earth, and many people contend there are already too many. While we can certainly continue to use science, and genetics, in particular, to increase our life expectancy, it may be that we are butting heads with Nature and that the balance that has existed on earth between the planet and the organisms that live on it, will be affected, perhaps resulting in problems we cannot, or will not foresee.

References

NIH. (2011a). Learning about Tay-Sachs disease. National Institutes of Health: National Human Genome Research Institute. Retrieved from http://www.genome.gov/10001220.

NIH. (2011b). NINDS Tay-Sachs disease information page. National Institutes of Health: National Institute of Neurological Disorders and Stroke. Retrieved from http://www.ninds.nih.gov/ disorders/taysachs/taysachs.htm. 

Mayo Clinic. (2011). Tay-Sachs genetic testing basics. InteliHealth: Genetics. Retrieved from http://www.mayoclinic.org/tay-sachs-disease/treatment.html.