Systems biology—how things work
By looking at how living things operate together, you see things you never saw before.
“The world is warming, and human activity is affecting it. The disappearing polar bears are the canaries in the mine. We live in that mine.”
MATTHEW EDLUND M.D.
Contributing Columnist
health@lbknews.com
Systems biology is a new field you’ve probably never heard of that should change the way we live. It studies and models how different parts of life work, interact, communicate and operate together. It provides a very different way of thinking than the standard reductionist approach in the biological sciences, where smaller and smaller parts are studied in more minute detail.
In molecular biology, the change has required opening up the field to mathematicians, physicists, chemists and computer scientists. Getting them to work together is itself a system problem. Yet new eyes lead to new approaches. How DNA works was figured out by X-ray crytallographers, biochemists, plus physicists like Francis Crick, coming to study the biophysical nature of genes. For system problems like cancer and the often “unpredictable” side effects of drugs, such approaches are necessary.
At present, molecular biology finds itself a bit stuck. How do you figure out how tens of thousands of genes make thousands of proteins that in turn control each other’s processing and synthesis? You do the same thing mathematicians and economists do when faced with huge piles of data and too many variables—you make models.
It’s a bit like trying to understand the American economy if you only possess a very primitive map of the country. You know there are cities out there like New York and Chicago. You know there are highways between them. But you don’t know what goes on those highways. You know of cars, and perhaps trucks, but you’ve no idea who drives them or what they carry. You know nothing about communications devices like radio or television or even telephones. You sense there is something like money, but you’ve no clue as to banks or credit. You’ve got an inkling there’s a thing called climate, but you’ve no concept of how important or unimportant it is.
It’s become evident you need new systems approaches to figure out how the cell, organs and body work together. Scientists and mathematicians have created new explanatory systems, like chaos theory and complexity theory, to help. They explain how small changes in one arena have huge effects on the whole. A minor example is rheumatic fever. Parts of hearts cells are misread by the immune system as pieces of streptococcal bacteria. An otherwise harmless infection then creates an extreme immune overreaction, leading to heart disease and eventual death. The chain of causation for such an event takes in dozens of subsystems of the immune system, cell communications and brain-immune effects. The most important parts involve how biological systems work as forms of information.
Is this tough to understand? Absolutely. But when you have a sense of how such things work, you’ll be able to figure out why thalidomide causes limb abnormalities only if ingested 28 to 42 days after conception; why phen-fen cut people’s weight at the same time it destroyed heart valves; why heavily radiating one group of cells leaves them untouched, yet kills cells nearby, unradiated cells.
A different, non-biological example of how such systems operate is the modeling devised to explain global warming. Though in many ways far less complicated than what systems biology is trying to tackle, climate change involves hundreds of different variables and dozens of different ways of putting them together.
The models that result frequently differ in their expected results. If you change the assumptions just a little, the Arctic summer ice cap disappears in 2040, 2060 or 2090.
Yet while there is overall disagreement about some endpoints, there is widespread agreement among scientists, though not corporations or politicians, of what the different models mean. The world is warming, and human activity is affecting it. The disappearing polar bears are the canaries in the mine. We live in that mine.
The different models of global warming change as the data improves. More data, more information, more predictive models. These models will then help provide the information we need to prevent, modify and adapt to the world’s changing climate.
Similar results will occur with systems biology. By looking at how living things operate together, you see things you never saw before. They should improve personal and public health in ways not yet thought.
One part of this emerging picture is that of bioenergetics, or how energy flows through the cells and the body. Though many of the specifics are not worked out, they possess implications for daily life in areas like food, activity and rest.
