Main content start
decoration image
KAN Yuet Wai




KAN Yuet Wai

Doctor of Science
honoris causa

It is indeed a great privilege for me to speak today on behalf of the four honorary graduates, I thank Your Excellency, the Vice-Chancellor and the Senate for bestowing upon us the highest degrees of the University of Hong Kong. We are especially honoured because this is the first congregation presided over by our new Chancellor, Sir David Wilson. 1987 also marks the centennial of my alma mater, the University of Hong Kong Medical Faculty, and the year in which we pay a special tribute to our first graduate, Dr Sun Yat-sen, the father of modern China.

Since leaving Hong Kong in 1960, I have devoted a great deal of my time to medical research. I am fortunate to have chosen a field of study at a time when it was experiencing an unprecedented revolution in concept and technology. Never before have we had so many tools at our disposal to enable us to study man - both as an independent physical entity, and in relation to his past and future generations. I am speaking of the revolution in medical research as a result of the advent of biotechnology. I hope I will be able to impart to you a sense of the excitement these developments have generated, and convince you of the important role Hong Kong can play in this exciting new field.

In the field of medicine, the biotechnology revolution to which I refer has several different names, but I think the most descriptive is molecular medicine. To put it simply, molecular medicine refers to our understanding of the fundamental basis of how our genes work, and the application of this knowledge to the practice of medicine. The breakthrough in this regard originated in the 1950s when Watson and Crick discovered the structure of DNA, the blueprint of our inheritance. Four different types of molecules called nucleotides are the building blocks that make up DNA. Each human cell contains some three billion nucleotides which are organised into many thousands of functional units, called genes, and each gene directs a specific biological function. Given the enormous numbers of genes and their unique and diverse functions, how could we possibly hope to study each one individually? This seemingly impossible task came within our reach in the 1970s with the advent of so-called recombinant DNA technology, also known as gene-splicing. Human genes are inserted into bacteria, and as the bacteria grow and divide, so do the inserted human gene molecules until they become amplified many thousandfold. Whereas there may only be trace amounts of a particular gene product in our body, the technique of cloning yields vast quantities of genes in pure form for study. In consequence, there has been an explosion of information on the structure and function of genes in both normal and diseased states.

These new approaches had and continue to have a profound impact on many areas of medicine. Time will only allow me to present you with a few illustrations in the areas of genetic diseases, cancer, heart and infectious diseases, but I hope these will serve to arouse your curiosity and interest.

Genes that are responsible for many inherited diseases are being discovered literally every week, and new methods of early diagnosis are being devised. Let me use as an example one of the diseases on which I have spent a great part of my career, an hereditary anaemia called thalassaemia, which is common in people of Southeast Asian origin, as well as India, the Middle East, and the Mediterranean area. In Hong Kong, thalassaemia affects people who originated from the southern provinces of China such as Guangdong and Guangxi. If two parents both carry the gene for thalassaemia, there is a one in four chance that their children will be affected by a severe anaemia which requires regular blood transfusions throughout their lives. Through recombinant DNA technology, the gene responsible for thalassaemia, which is known as the globin gene, has been isolated, and we have learned that nature has made more than fifty separate mistakes which disrupt the normal function of the globin gene and cause the disease state. Most of these mistakes in nature, known as mutations, are produced by a change in one critical building block (or nucleotide) out of the more than three billion that comprise our genetic material, and it is through the amazing power of DNA technology that we are able to pinpoint the exact location and define the precise nature of the error. Knowing what kind of mutation causes the disease helps the clinician to identify people affected by the disease, and in counseling at-risk couples who want to have children. We can therefore design very specific tests to determine whether a person carries the mutation, and detect this change as early as the tenth week of pregnancy. The ability to define the mutation in the gene has given parents at risk of giving birth to children with genetic diseases the choice of bearing healthy offspring. This type of approach to prevention and genetic counseling is now possible for hundreds of genetic diseases, and offers the hope of finding better ways of treating genetic disorders in the future. Armed with the knowledge of which gene is involved in a particular disease, scientists are actively investigating how to replace the diseased gene with a health one in order to effect a cure. In cancer, scientists have learned that we all carry a number of different genes that regulate normal growth and development. A single nucleotide change in one or more of these genes, similar to the type of change that occurs in inherited diseases, may cause the gene or genes to malfunction. This in turn may lead to abnormal cell growth and cancer. This single nucleotide change may be brought about by environmental factors, or other, as yet unknown, insults to the gene. Sometimes the genes that control growth and development behave in an out-of-control manner because they have somehow multiplied many fold, or their orderly arrangement disrupted, or they have been invaded by a virus. Our comprehension of these diverse cancer-causing mechanisms has come about through the ability to isolate cancer genes and study what happens to them. Hopefully, we will soon be able to apply this knowledge to gain insights into factors that trigger these genes to malfunction, and be able to prevent the various factors that predispose an individual to develop cancer.

Great strides are also being made in our understanding of arteriosclerosis, a condition often associated with high levels of fat and cholesterol in the blood and one which can lead to coronary heart disease. The various genes responsible for control of fat and cholesterol levels in the body have now been defined, and understanding how they function may allow manipulation of the genes in order to decrease these levels. In addition, the gene that produces a naturally-occurring substance which dissolves blood clots has been isolated. This clot-dissolving substance has been produced in large quantities by recombinant DNA technology and appears to be effective in preventing damage to the heart muscle in heart-attack victims.

In the field of infectious diseases, new diagnostic tests using DNA technology are being devised which reduce the time needed for accurate diagnosis from days to hours - a crucial factor in some life-threatening situations. Infectious diseases that are epidemic in certain parts of the world may also be preventable through vaccines developed by recombinant DNA technology. One can separate the gene of a microorganism that causes disease from the gene that stimulates antibody production, and then use the antibody-producing gene to manufacture a vaccine. Vaccines against hepatitis which have been prepared in this way are currently available, and vaccines against malaria are being developed.

Another benefit derived from molecular medicine is in the production of large quantities of hormones or other naturally-occurring body chemicals that are normally present only in trace amounts. The genes for human insulin and human growth hormone have been isolated and these hormones are being manufactured in great quantity by recombinant DNA techniques. People who suffer from diabetes or from stunted growth due to a deficiency in their own hormone production have benefited from the availability of the synthetic material. Growth factors that stimulate production of blood cells can now be manufactured in vast quantities. These are being tested as therapeutic agents for treatment of anaemia and certain types of cancer.

In these few minutes, I have briefly just touched the surface of some of the newer developments made possible through the revolution in biotechnology. Incredible as it may seem, these advances have all occurred within the past ten years. Not only have they already begun to benefit the vast field of medical science, but they have also spawned a whole new biotechnology industry.

I think it is pertinent to consider what role Hong Kong should play in these exciting developments. Should Hong Kong participate, or should it leave this new and sophisticated technology to Europe, the United States, or to other parts of Asia where this technology is already in places, or is rapidly developing? I believe that Hong Kong should become actively involved in this new revolution. If the universities, the government, and industry can join forces, Hong Kong can play an important part in this new field.

A university has three interrelated functions: teaching, creative activity or research and public service. The impact of biotechnology on science and medicine is unparalleled by any recent development. The universities, therefore, simply cannot turn their backs on this area and still hope to fulfill their roles as academic institutions. It is imperative that they adopt biotechnology courses as part of their curricula, not only because biotechnology has become a necessary component of the educational process, but also because graduates will be better prepared for their future careers.

The government should also make a firm commitment to stimulate research in this area. I would like to echo Lord Todd's comment to the congregation last year that a good beginning would be to implement to the fullest the recommendations presented by Lord Flower's report on research support. I have no doubt that Hong Kong can become a fertile ground for original research in the health sciences. In addition to many of the more common diseases, Hong Kong has some special health problems that would be amenable to a biotechnology approach - genetic diseases such as thalasaemia, which I have already discussed, infectious diseases such as hepatitis, and cancers, particularly of the liver, stomach and nasopharynx. Research in these areas could directly benefit our own population, as well as the world at large.

Is biotechnology a viable new industry for Hong Kong? I am quite confident it could be. The resourcefulness of Hong Kong businessmen is legendary. Their innovativeness, adaptability, and efficiency have launched many new industries in the past few decades. The electronics, watch, garment, and toy industries to name a few, have had enormous impact throughout the world. Furthermore, Hong Kong's strategic location, its excellent financial, transportation, and communication facilities would make it an ideal centre for biotechnology in the Far East. Government-supported research and university-trained personnel will provide the necessary components to support a whole new industry, one which can only add to the prestige and prosperity of Hong Kong.

Is the talent already available to launch such a venture? One has only to look at any reputable scientific journal to see that a significant number of articles are authored or co-authored by Chinese scientists, many of whom received some part of their education in Hong Kong. A large number of these scientists, however, reside and work abroad. Hong Kong will need commitments from the government to set up facilities, from the universities to supply the intellectual environment, and from industry to provide the impetus to attract these overseas graduates back to Hong Kong. In concert with the talents already in place locally, these scientists can implement the educational and research programmes to begin this venture.

We have seen how the biotechnology revolution has already stimulated research and helped us understand many diseases. It has produced new diagnostic tools and therapeutic agents for health car and created a whole new industry. Cooperation between government, universities and industry has already been successful in Great Britain and the United States. By combining the efforts of the government and academic sector with the vast resources of its business community, Hong Kong could launch its own biotechnology industry and become a centre of excellence for southern China and Southeast Asia for many years to come.

decoration image