The father of the science of evolutionary medicine, Randolph (Randy) Nesse, has a favorite aphorism: “Medicine without evolution is like engineering without physics.” In the same way that it would be impossible to imagine building the Rosetta spacecraft, sending it 300 million miles to rendezvous with Comet 67P, and successfully deploying the Philae lander, chock-full with sampling instruments, without physics and specifically Newtonian mechanics, it proves similarly impossible, for instance, to get to the root of the horrifying scourge of Alzheimer's disease unless we ask deep and fundamental questions, informed by evolution, about what the alleged poisonous plaques of beta-amyloid protein are doing in the brain in the first place. Is amyloid pure pathology or does it have an vital evolved function in the brain? In this sense, Nesse has frequently claimed that the value of evolution to medicine is that it while it may lead directly to changes in medical practice or indeed to new therapies, more fundamentally its value lies in explaining why things are as they are. That is why Nesse argues that evolutionary biology should be the foundation and cornerstone for medicine as it should be for all biology. This book is an attempt to put yet more flesh on the bones of Nesse’s idea that evolution is the “physics” of medicine. I describe the evolutionary background to seven areas of human disease that are causing deep contemporary medical concern to explain why they exist in the first place—why things are how they are - and how evolution might help us to combat them. I hope it will leave readers with a new respect for evolution as the prime mover for the structure and function of human bodies, even if it does, on occasions, cause them to break down and drives us into ER!

Each chapter is built around the sometimes harrowing but always inspiring personal stories of people trapped in the disease process in question. Each chapter provides an evolutionary explanation for why the disease has come about, and each chapter shows how medical researchers, using powerful insights gained from thinking about disease in an evolution-informed way, are charting our way out of it.

How a modern version of the hygiene hypothesis - called the "old friends" hypothesis - explains why the Western world is riddled with allergic and autoimmune diseases, and what we can do about it.
How evolutionary theory explains why the battle between the different selfish genetic interests of mothers, fathers, and fetuses causes low fertility and can lead to diseases of pregnancy like recurrent pregnancy loss, preeclampsia and gestational diabetes.
What is the relationship between the fact that we have evolved to walk upright - our bipedalism - and a range of orthopedic illnesses?
Creationists have always used the example of the "irreducible complexity" of the human eye as the bedrock of their argument that God designed the human body, not evolution. Modern developmental biology, however, not only strongly rebuts creationism but explains the astonishing secret of how the recipe for eyes actually unfolds from within the developing eye itself, not from external influences, and is leading to cures for eye diseases like retinitis pigmentosa and macular degeneration.
How does cancer evolve so remorselessly towards malignancy that it is proving almost impossible to cure? Cancer evolution can be so extreme and drastic it is forcing us to re-write the rules of evolution by resuscitating a heresy from the 1940s.
Why are coronary arteries evolution's answer to feeding our powerful, muscular hearts with the food and oxygen they need and how has this led to the continuing pandemic of coronary heart disease?
Research into curing Alzheimer's disease has become hopelessly bogged down and billions of dollars have been wasted trying to turn the "amyloid hypothesis" into therapy. Can we use evolutionary thought to better explain why dementia comes about in a way that might lead to fresh hope for a cure?


Sunday, 6 March 2016

The Most Promising Cancer Therapy in Decades Is About to Get Better
This is the clearest article I have yet seen on the very promising research recently published by Charlie Swanton and Nicky McGranahan of the Crick Institute, Sergio Quezada from UCL, and various colleagues. Swanton is a prominent "evolution in cancer" researcher and this represents the first steps to try and beat cancer evolution via immunotherapy. The reason why eradicating cancer lies at, or even beyond, the capability of modern medicine lies in the evolution of heterogeneity within tumours. As cancers develop they become differentiated into a number of sub-clones of cancer cells which have all diverged from each other in their genetics. They will bear different mutations and, as a result, will bear different types of protein antigen markers on their surfaces. An immunotherapy targeted at one set of these markers may be initially successful and kill off a lot of cancer cells, but it will inevitably be beaten by this heterogeneity and a sub-clone resistant to the therapy will arise and take over. To design a really effective therapy against ALL the cells in a tumour you literally have to find a way through the old saw "you can't see the wood for the trees". In direct comparison to Darwin's tree of life, where the diverging different forms of the animal kingdom, for instance, can be seen as the terminal twigs on a rapidly branching tree from one initial trunk, these researchers have realised that they can identify the protein antigen markers corresponding to so-called "trunk" mutations that have occurred very early on in the cancer and which endure even when proliferating and diverging cancer cells start bristling with a vast range of neo-antigens. They have already seen T cells capable of targeting these antigens, inside tumours, which are hand-tied by the cancer cells. They are now hoping to find ways of growing the T cells outside the body, reinserting them, having removed he chemical brakes on them, in a new brand of personal medicine capable of attacking all the genetically-different cancer cells in the tumour.

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