It’s Time to Admit That Genes Are Not the Blueprint for Life
By Denis Noble
Published on 05 February 2024
DNA sequencing has become routine, but the roles of individual genes can be hard to pin down. Philip Ball, in his latest book ‘How Life Works: A User’s Guide to the New Biology’, challenges the oversimplified view of biology often presented to the public. He argues that scientists must set the record straight about the complexity of biology, as it affects policy, health care, and trust in science.
Ball criticizes the metaphor of living systems operating like machines and genes being their code. He emphasizes the importance of being open about the complexity of biology, including what we don’t know. He believes that public understanding has far-reaching implications.
When the human genome was sequenced in 2001, it was widely believed to be an ‘instruction manual’ for life. However, it turned out that the genome is not a blueprint, and most genes don’t have a pre-set function that can be determined from their DNA sequence. Their activity depends on external factors, such as diet and the environment in which the organism develops. Additionally, 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.
Ball highlights that it is an oversimplification to say that genes cause specific traits or diseases. He points out that organisms are extremely robust, and a particular function can often be performed even when key genes are removed. For instance, the heart retains its rhythm even if the HCN4 gene, which encodes a protein that acts as the heart’s primary pacemaker, is mutated.
Another metaphor that Ball criticizes is the idea of a protein with a fixed shape binding to its target being similar to how a key fits into a lock. He notes that many proteins have disordered domains, making them versatile communicators that can respond rapidly to changes in the cell.
Ball’s book serves as a must-read user’s guide for biologists and non-biologists, shedding light on the intricate and fascinating nature of biology. It challenges the conventional understanding of genes and living systems, urging scientists to be more open about the complexity of biology and its implications for various aspects of society.
