The Dance of Life
Authors: Magdalena Zernicka-Goetz and Roger Highfield
This most exciting book is nothing less than a fantastic voyage into the early development of the embryo, what the authors refer to as a thrilling dance of life. Depicting one of the most incredible transformations in nature, the book describes what actually transpires when egg and sperm cell fuse, and what drives their incredible metamorphosis into a fully fledged living creature. Portraying this as ‘one of the greatest mysteries of biology’ – ‘hidden in the shadows’ until recently – the first author describes in remarkable and exciting detail her ground-breaking research which helped to shed light on ‘how an embryo with no brain, consisting of a single cell, manages to divide and grow to become the most sentient being that we know of’. With a single-minded determination, the author, a mammalian development biologist, sought to understand ‘the fate of all individual cells’ in the embryo as they either become ‘the embryo proper…or part of the placenta or simply disappeared along the way’. What she documents is however not just her ‘surprising’ discovery that ‘the fate of cells is predictable earlier than expected’, but it is also an epic tale of the challenges and scepticism that trailed her landmark discoveries. More than just a review of early embryology, the book is a commentary on the whole scientific enterprise as reflected in the author’s continuous striving to strike a balance between finding her distinctive ‘scientific voice‘, and protecting herself from the hazards of her profession (pages 1-2, 33-36, 154 and 221).
Perhaps the most fundamental concept the book explores, right at the heart of the embryological process, is that of symmetry breaking, the key to how a few identical cells could generate such a diversity of cell types that eventually form the different tissues and organs of the body. To break open this so-called ‘black box of mammalian development’, the author studied the evolution of the mouse embryo, and what she discovered ended up overturning ‘the prevailing dogma‘ that ‘the seeds of symmetry breaking occur relatively late in the development of the mammalian embryo’. In a very compelling and enlightening narrative, she demonstrated that the foundations of symmetry breaking are established much earlier, indeed as early as the entry of the sperm cell into the egg. This entry point, which the author ingeniously mapped by using fluorescent beads, turns out to be influential in determining the destiny of individual embryonic cells. Similarly intriguing are her discoveries that the axis of orientation of the first cell division dictates which pole of the embryo will develop into the placenta, and that the unequal distribution of an enzyme, a transcription factor, and a gene, determine which part of the embryo will become the baby (pages 2, 8, 103-109, 16, 86-102, 33-35 and 57).
Beyond providing a comprehensive account of the mechanisms driving the early development of the embryo, the book also constructively sets out the practical implications of this understanding on human reproduction. Perhaps the most imperative ramification in this regard is on the field of in-vitro fertilisation (IVF), a process which the author asserts is currently ‘inefficient, expensive, and stressful’. The author attributed these shortcomings to the way preimplantation genetic diagnosis (PGD) is used to weed out and discard countless early ‘abnormal’ cells which she asserts ‘may well have developed into normal babies’ because embryonic cells possess the capacity ‘to self-correct and develop normally’ . It was therefore heartening when she outlined how research works such as her own, are providing ‘an objective, quick, and simple way to measure the developmental potential of an embryo’. An example of her own promising research in this regard is how she used particle image oscillometry to predict ‘whether a specific egg will develop into a healthy mouse’. The promise of these types of breakthroughs is that they will wipe the tears of the vast majority of infertile couples who currently go through the IVF process but ‘will not have a baby at the end’ (pages 92, 210, 205-208).
As insightful as her account of embryology is, her perceptive portrayal of the wider scientific process is equally revealing, portraying several inspiring high points, and numerous hard truths. In this way, she graphically conveyed the excitement that comes with doing science, a process she conceived as playing out in three acts – ‘coming up with a new idea‘, devising the ‘experimental work to confirm or challenge the idea’, and submitting papers to the journals that would ‘let your discovery see the light of day’. Whilst she highlighted the inevitably exacting requirements for a successful career in science -‘huge passion’, determination, patience, grit, and ‘shining optimism’ – she also appreciated the huge role mentors such as Nobel Prize winners John Gurdon and Martin Evans have played in supporting her research work. She similarly acknowledged the importance of innovative technologies without which, she admitted, her breakthrough discoveries would not have been possible; examples of such technologies she explored are green fluorescent protein (GFP) which was developed by Nobel Prize winners Osamu Shimomura and Martin Chalfie; confocal microscopy whose ‘stunning three-dimensional, colorful images brought home to me the power of visualisation in research and the enlightenment that comes with scientific art’; and time-lapse movies which monitors cell fate thereby enabling her to track ‘the ancestry of every cell’ (pages 153-154, 24-42, 37-38, 31, 93-94 and 112-113).
In contrast to the stimulating nature of her laboratory research work is the despairing and seemingly endless challenges that come with the territory. In this respect, the author described the failures that inevitably presaged her successes, and she illustrated this for example when she recounted her initial setbacks in getting GFP ‘to work in mammalian embryos‘. She used these types of disappointments to emphasise that ‘failure really is the order of the day when doing research’ and ‘we have to learn from each failure so we can move forward‘. But beyond these expected stumbling blocks, the author also called attention to the challenges of the underrated and seemingly mundane demands that come along with doing science, from ‘the relentless pressure to solve scientific problems’, to the responsibility of marshalling enough ‘enthusiasm to motivate your team’. Perhaps even more discouraging is having to accept ‘the anonymous criticisms of referees’, and having to engage in the cumbersome and time-consuming research funding application process. The author was also scathing of the stringent legal and ethical research guidelines which she said stifle human embryo research, remarking facetiously that had they been in place in the 1960’s, they would have impeded the breakthrough of in-vitro fertilisation made by Robert Edwards and Patrick Steptoe (pages 39, 56, 218-219, 103 and 127-139).
Alongside the depiction of hard research and scientific work, the book also conveyed the human and personal dimensions of the author especially as a mother and as a woman scientist. In this context for example, she described her experience of pregnancy at the relatively old age of 42 years, along with the disconcerting discovery at chorionic villus sampling that there were extra copies of chromosome 2 in a quarter of her embryonic cells that were sampled – a finding which was not confirmed by a subsequent amniocentesis. Similarly unsettling for her was the way in which her ‘paradigm-busting‘ discoveries, which went against the dogma of the day’, were ‘erroneously misrepresented‘, opposed, and attacked by her peers, a situation that resulted in ‘an ugly dispute‘ that ‘would weigh heavily on me for years’. Whilst acknowledging that ‘science is built on skepticism‘, she nevertheless believed that her work, along with that of many other women, was disproportionately questioned because of her gender (pages 141-153, 57, 102, 223 and 213-217).
The book starts rather slowly but once it picks up the content is really breathtaking. The authors’ depiction of the scientific process is inspirational without downplaying the hardships, the failures, and the challenge of peers. The first author elucidated quite clearly how mechanisms operating in the earliest stages of embryological development determine cellular fate, and in the process she described how her research contributed in breaking down decades of scientific dogma and shedding light on what is a most critical time in human development. The book is an exhaustive assessment of what is obviously a rapidly growing field, and it provides insights into the far-reaching practical impact this will have on medicine in particular, and society as a whole. Whilst the author highlighted the effect of gender prejudice on her career, the book doesn’t give enough supporting evidence for this; even though her experience is similar to that of many scientists of either gender who have dared to challenge received wisdom, this was perhaps a missed opportunity to clearly demonstrate how misogynist practices discourage and hold back female participation in science. Similarly, the book did not elaborate on the details of the research disputes that left such a lasting impact on the author. These apart, the book is well-written, the subject thoroughly explored, and the implications of the themes clearly outlined.
This book is a refreshing insight into the origins of life, explaining how embryonic cells set out to achieve their different fates very early in the reproductive process. The book also paints a clear picture of the scientific process itself, highlighting its laudable principles and chastising its less endearing practices. The book’s depiction of the potential benefits of early embryonic research, such as on in-vitro fertilisation, highlights the practical value of reproductive science to human progress. This is an inspiring and enlightening book with significant consequences for healthcare, and I recommend it to all doctors.
Publisher, Place, Year: WH Allen, London, 2020
Number of chapters: 11
Number of pages: 289
Star rating: 5