Viewpoint

Where are the Gene Doctors?

Martin Kennedy

Your father has been struck down by an incurable disease that causes slow but inexorable mental and physical deterioration. Other members of your family suffered in similar ways, and it seems obvious that this is a heritable condition. Is it possible that your children have inherited the disorder? Is there a means of testing for inheritance of the disease before it strikes? If you take the test and discover that you will be afflicted within a few years, how will you cope with this knowledge? Who can help you to understand these issues?

There is a group of specialist medical professionals who are trained to answer these kinds of questions. Clinical geneticists, usually supported by genetic counsellors with postgraduate qualifications in genetics, are able to offer advice about all types of inherited or congenital disorders. This advice extends from diagnosis through to therapy and includes counselling on issues of inheritance, prenatal diagnosis, and genetic testing. They are regarded as necessary specialists in any modern, hospital-based system of health care. Clearly then, these are the professionals you need to turn to for advice on the sorts of questions posed above. This is not a problem if you live in almost any developed part of the world, with the exception of the South Island, New Zealand.

Why are there no clinical geneticists in South Island? Is this really a deficiency in our health system, or can medical specialists in paediatrics, oncology, cardiology, and so on, cover the territory of medical genetics effectively? Aren't genetic problems restricted to only a few unfortunate families or individuals, so that economically speaking clinical geneticists are not really justified?

It is a misconception that genetic disorders affect only a few people. It is true that genetic diseases tend to be rare, but there are many, many genetic disorders -- about 4,000 diseases are known. The diseases that are clearly inherited usually arise because of damage to a single gene. The most common disease of this type is cystic fibrosis (CF), a serious respiratory disorder which affects roughly one in every 2,000 people. Although there are few CF sufferers in New Zealand (about 320), close to 130,000 people in this country are unsuspecting carriers of the faulty gene. Only when two of these people conceive a child with the disease will they become aware that they are carriers.

In addition to the single-gene diseases, there are many that are more complex in their patterns of inheritance. They arise because of the influence of more than one gene, or because of interactions between one or more genes and other non-genetic factors. Included in this group are various psychiatric disorders, various heart problems, some types of diabetes, and some types of cancer.

Finally, numerous congenital disorders exist. These conditions, although not necessarily inherited are abnormalities in physiology or body structure that are present at birth. Some are caused by genetic damage, some by problems during pregnancy or birth, and others are of unknown cause.

Various statistics can be used to describe the impact of genetic disease on the health of a population. All of these numbers tend to overlook the human cost, in terms of suffering and grief that ensue, but they are the sort of numbers that economists and politicians should heed. About 2,000 children are born every year in this country with genetic or congenital diseases, many of which are serious and result in severe disability or premature death. This represents about 3% of all live-born infants in New Zealand. Genetic disorders cause about one-third of childhood hospital admissions, and it is estimated that something like 60% of the population will be affected during their lifetime by disorders with a strong genetic component. Our genes are the foundation on which our health is built. Investment in the genetic well-being of a population should be a prominent component of the health-care budget in this country as it is overseas.

Genetic disorders can affect every organ and every aspect of our physiology; they may cause deafness, vision defects, heart or muscular problems, brain, nerve, bone or skin disorders. Some cause minor inconvenience, others are lethal, and because most of these disorders result from some fundamental flaw in the biochemistry of our cells or from misprogramming during embryonic development, then cures or effective therapies are rare.

Because genes are inherited, the impact often extends to our children and other close relatives. This means that the psychological burden of genetic disease is disproportionately borne by those families with more than one afflicted member, and often the unaffected members suffer guilt, fear for the future of their own health, and fear of having their own children. In these families, the ability to diagnose the disease, to detect the presence of the disease gene either prenatally or presymptomatically (before signs of the disease appear), and to understand the cause of the disease are of enormous significance. In the parlance of contemporary health economics, the ability to offer prenatal diagnosis and reproductive choice in such families is extraordinarily cost-effective. This is why clinical geneticists are important.

Genetic illnesses often fall within the territory of medical specialties such as paediatrics, oncology, obstetrics, neurology and haematology. Professionals in these areas are well equipped to understand and treat the disorder, but they will not necessarily understand much about the genetics. Genetics is not a major part of medical education in this country, and any expertise that medical practitioners have in genetics tends to be obtained after they leave medical school. The level of understanding most likely depends on the practitioner's personal motivation to understand the issues; many simply do not have the time or the inclination to learn about the complexities of genetics.

To compound the problem, molecular biology is powering an extraordinary renaissance in our understanding of human genes. This new knowledge is pouring from research laboratories faster than it can possibly be assimilated into clinical practice. The result is that few medical practitioners in this country are qualified or competent to cope with the issues raised by genetic testing, nor are they necessarily qualified to offer precise guidance on genetic issues. There is no doubt that the standard of care offered to those suffering from genetic disability by general practitioners and medical specialists would be significantly enhanced by the local presence of a clinical geneticist, or at the very least a qualified genetic counsellor.

Present international guidelines dictate a minimum of one full-time medical geneticists per 500,000 population, each assisted by two full time genetic counsellors.

How do we rate? In South Island, not at all; we are equivalent to any Third World country. New Zealand has two clinical geneticists and three genetic counsellors -- all located in North Island. Direct, accessible, and personal genetic advice to the 600,000 people in the South Island simply does not exist.

If you feel that your need for genetic advice has been poorly met then you should be lobbying for an adequate genetics service for Christchurch. Talk to your MP, tell your clinician that you would like to see such services here, or write to the Southern Regional Health Authority or the Core Services Committee, to voice your dissatisfaction and find out why these services are unavailable in Christchurch.

The New Zealand Genetic Support Coalition, which aims to provide a united voice for all people with genetic conditions and their supporters, can be contacted through Howard Esler, 6 Peter Mulgrew Street, Avondale, Auckland 7 (Tel: 09-627-9137).

Dr Martin Kennedy works in the Cytogenetics and Molecular Oncology Unit, Christchurch School of Medicine.