Nature: The view of biology often presented to the public is oversimplified and out of date. Scientists must set the record straight, argues a new book. How Life Works: A User’s Guide to the New Biology Philip Ball Pan Macmillan (2024) For too long, scientists have been content in espousing the lazy metaphor of living systems operating simply like machines, says science writer Philip Ball in How Life Works. Yet, it’s important to be open about the complexity of biology — including what we don’t know — because public understanding affects policy, health care and trust in science. “So long as we insist that cells are computers and genes are their code,” writes Ball, life might as well be “sprinkled with invisible magic”. But, reality “is far more interesting and wonderful”, as he explains in this must-read user’s guide for biologists and non-biologists alike. When the human genome was sequenced in 2001, many thought that it would prove to be an ‘instruction manual’ for life. But the genome turned out to be no blueprint. In fact, most genes don’t have a pre-set function that can be determined from their DNA sequence. Instead, genes’ activity — whether they are expressed or not, for instance, or the length of protein that they encode — depends on myriad external factors, from the diet to the environment in which the organism develops. And each trait can be influenced by many genes. For example, mutations in almost 300 genes have been identified as indicating a risk that a person will develop schizophrenia. It’s therefore a huge oversimplification, notes Ball, to say that genes cause this trait or that disease. The reality is that organisms are extremely robust, and a particular function can often be performed even when key genes are removed. For instance, although the HCN4 gene encodes a protein that acts as the heart’s primary pacemaker, the heart retains its rhythm even if the gene is mutated. Another metaphor that Ball criticizes is that of a protein with a fixed shape binding to its target being similar to how a key fits into a lock. Many proteins, he points out, have disordered domains — sections whose shape is not fixed, but changes constantly.”