A Day with Kary B. Mullis
Six Apes and How to Win the Nobel Prize
An interview has different advantages in comparison with a talk or an article. At least two persons participate. G.I.T. Laboratory Journal Europe visited Kary B. Mullis and his wife Nancy Cosgrove-Mullis at their home in Newport Beach, California.
When you prepare an interview you draw up a list of questions. You plan to ask in defined order, connected also if they touch completely different topics. In this interview I just asked two questions and then Kary Mullis followed my train of thought without knowing anything about it. Maybe I didn't realize how obvious my thoughts were, but this is very unlikely, because the topics we talked about started with the invention of Polymerase Chain Reaction (PCR), but quickly approached through the field of biology, chemistry, physics and the structure of the universe. In the end all my questions were answered, one after the other, and nearly exactly in its planned order. But it is useless to cut down something like this to an interview. Hence, I decided to form an article that describes some of the impressions and inspirations I got from my day in Newport Beach, California.
Kary Mullis invented the wheel of molecular biology by developing the PCR. PCR is in principle simple, like most important ideas. You just need two single stranded oligonucleotides, one of them has to be complimentary to a short sequence on one strand of the DNA. The other has to be complementary to a short sequence on the second strand. To run the reaction you need a DNA polymerase, these two oligonucleotides, all four triphosphonucleotides the DNA is made off and a template DNA. If you heat double stranded DNA up to 90-95°C the two complimentary strands will separate from each other. If the temperature sinks, the small single stranded oligonucletides can anneal to the melted DNA strands and the polymerase adds nucleotides one by one until the template DNA is completely saturated with the complementary sequence. You can repeat this cycle again and again, thereby doubling the DNA sequence between the two primers in each cycle producing enormous amounts of the targeted sequence. Essentially all techniques in molecular biology and genetics depend on large amounts of DNA of a specific sequence.
Imagine you have to produce this without PCR. Not a single genome would be sequenced today.
While Kary Mullis was driving in his car from San Diego to Mendocino, he was thinking of possibilities to use oligonucleotides for the identification of genetic diseases, or the application of oligonucleotides in general. At this time he was employed by a small but innovative company -Cetus Corporation- providing all kinds of services to biochemists and molecular biologists. There he led a department of five employees, which was responsible for oligonucleotide synthesis. A few weeks before, he purchased a brand new synthesizer. This device enabled the department to produce twice as much oligonucleotides per day, his crew needed a month before the installation. So the question was, what to do with all these oligonucleotides?
Have you ever driven on an American highway? It can get really monotonous and your thoughts might drift away. This is exactly what happened to Kary Mullis. He really understands DNA, not as a simple strand with an endless number of four characters in different arrangements. He understands its three dimensional structure, its physical properties and the resulting behavior under changing conditions. So while driving his mind played around with long double strands and shorter single stranded DNA fragments, put them together under certain conditions and turned them around under different circumstances.
Some of the best ideas in human history were born like this. Our brain uses free capacities to play with information it collected before. And then suddenly all puzzle fragments fit. This is what August Kekulé described on dreaming the structure of Benzol. „I turned my seat to the fireplace and start to doze. Atoms swayed around. This time smaller groups stayed in the background. My inner eye, stained by comparable experiences, distinguished larger entities of manifold forms. Long rows somehow condensed. Everything moves, winds and spins snake-like. And suddenly...." (translated from Anschütz 1929, II, p. 942).
In such a precious moment everything perfectly fits together - a flash of inspiration and you know that it will work. Kary Mullis describes that in this moment he lost control over his car. Hence, by a whisker, PCR would have died just a second after its birth, evenly distributed throughout highway 128 at milestone 46.58 together with the grey matter that was responsible for this outstanding idea. But Kary Mullis could stop the tossing and turning car, and the passing cars left behind a genius who suddenly realized that he will win the Nobel Prize.
Kary Mullis is a scientist. What is it all about being a scientist? Being insatiable curious. Feeling free to do and to say what you want, to call a spade a spade. Saying things the way they are, or at least how you believe they are. To say things that are out-of-favor, or scandalous, even when people don't want to hear about it. As a scientist, you have the responsibility to contradict when somebody tells things that are not true, or not proven. Sometimes the truth hurts. But people don't want to be hurt. And when they get hurt they might strike back. Kary Mullis hurt people by telling the truth. Like for example with his opinion on global warming. Along with other scientists he is not convinced that CO2 produced by humans can cause global warming. He is not even convinced that global warming happens at all. Mankind measures temperature systematically since the middle of the 19th century. These data are now used to calculate the climate of the past 5,000 years and the next hundred years.
Just recently the director of the Climatic Research Unit (CRU) of the University of East Anglia, UK, Phil Jones, gave an interview to the BBC, where he answered "yes" to the question, if he agrees that there was no statistically relevant global warming between 1995 and 2009. In response to the question if there was a global cooling between 2002 and today he answered also "yes". But he still stated that he is 100% confident that the climate is warming. Personal confidence is different from scientific evidence. Fact is that the collected data on temperature change throughout the millennia is extremely poor in comparison to a complex system as the climate. How reliable prediction of climatic changes are, everyone can easily imagine by thinking on the reliability of a four week weather forecast. These predictions are based on datasets on temperature, wind speed, humidity, atmospheric pressure, etc. - measurements and data that are not available before the mid 19th century. Kary Mullis asks if it might be better to spend money for research on the topic instead of wasting money to avoid CO2 emissions in a situation when there is no clear evidence of climatic changes at all.
How misleading such predictions are, can be described by the scientific sight on molecular evolution. To have an idea on how evolution works on the genetic level, billions of Dollars were expended to sequence the most important (most supported) metazoan genomes. Drosophila melanogaster (Fruit Fly), Caenorhabditis elegans (Nematode worm) and Homo sapiens sapiens. In correspondence to the genetic sequences, morphological complexity, and the supposed position in the tree of life, it was assumed that the number of genes increased during metazoan evolution, due to gene and genome duplications and the adaption of the new genes to a new function. Today this scenario is widely accepted in the scientific community. But it is wrong. In an increasing number of genomes, which are much simpler on the morphological level than the worm or the fly, a very much higher number of genes were identified. For example, the genome of one of the basal most metazoan organisms, the sea anemone Nematostella vectensis contains much more genes than the worm or the fly. Its genome contains genes for structures that were not even evolved when the Sea Anemones diverged from the other animals. Like genes for eye-development, mesoderm specification, or the patterning of bilateral symmetry. This shows that at least in some cases the loss of genes is important for evolution, but not the number itself.
How can genomes evolve without Darwinistic pressure or independent of morphological changes? Kary Mullis plays with the idea that the genomes' evolution is partly decoupled from the morphological evolution, shedding new light on the term ‘selfish gene'. Animals evolve because they are forced to adapt to environmental factors. Genes get changed in their sequences due to radiation, presence of certain chemicals or accidents in the copying procedure, statistically even distributed. This demonstrates that completely different evolutionary forces act on animals and their genes.
A topic often discussed in molecular biology is the question whether DNA, RNA or proteins were the first functional molecules enabling enzymatic activity and heredity. Maybe DNA, RNA and proteins were formed separately and then worked together in a kind of symbiosis. This sounds strange but it is also the case for the endosymbiont-theory that explains the existence and structures of mitochondrial and chloroplast DNA.
Single stranded RNA and DNA-molecules can have a function themselves. This can easily be seen in the function of aptamers, the current playground of Kary Mullis' intellect. Aptamers, a word merged from the latin word aptus (to fit) and the greek word meros (domain), are short single stranded oligonucleotides of 25 to 70 nucleotides. Each one has a unique 3-D-structure in dependence of its sequence. The structure of one aptamer may exactly fit and strongly attach to a target-structure. When you start with 1015 aptamers that differ in sequence and structure, and put them together with the target you wish to address, you have a good chance that one or some of the aptamers will bind to it. The specifically binding aptamer can be identified, amplified and optimized. The product is in specificity and affinity comparable with an antibody.
Aptamers are already used commercially, for example as a detection method for cocaine, or as a drug against the degeneration of the Macula. Kary Mullis and his co-workers aim is to link the action of the aptamers as specific grippers directly to the mammalian immunesystem. Thereby, producing a stable immunization against any given target with a single application of the drug. In comparison with today's strategy for the development of vaccines, which is dependent on the growth of viruses in a chicken egg, this will have an enormous impact on the health care system around the world.
The system already works perfectly in the rat model. I guess we will hear more about Kary Mullis soon.
The few pages in G.I.T. Laboratory Journal Europe are by far not enough to report on details or more than a few impressions of a four hour speech with this brilliant scientist, this sharp and clear analyst and this fascinating and warm person, Kary Banks Mullis. One of his scientific advisors called him a ‘wide angled genius' at the beginning of his scientific career. But he is definitely more than this, a role model for truth in science, a truly loving husband and a real nice guy.