Ever wonder why hereditary diseases are so common when natural selection is supposed to get rid of harmful genetic traits? One possible answer might be that the conditions that we think of as diseases today actually gave our ancestors an evolutionary advantage in the past. When the choice is a long life with a disease or a short one without it, evolution usually favors the former.
These topics are explored in this week's podcast with Sharon Moalem, Ph.D., the author of a new book entitled Survival of the Sickest: A Medical Maverick Discovers Why We Need Disease, published by William Morrow. Dr. Moalem maintains that when you take the evolutionary long-view, many diseases are really complicated blessings, not simple curses. He shows why one generation’s evolutionary solution is another generation’s evolutionary problem, especially when people no longer live in the environment that their bodies adapted to through evolution.
Dr. Moalem discusses the evolutionary advantage of such diseases as hemochromatosis and Type I diabetes and talks about the evolutionary tradeoff involving the ApoE4 gene and vitamin D production and the risk of developing heart disease, stroke, and Alzheimer's. He also explains the significance of the human genome containing so much non-coding or so called junk DNA in relation to health and disease.
Be sure to listen to Dr. Moalem's podcast then return to the blog and give your thoughts on the following question:
In his book, Dr. Moalem tries to answer a key question: If natural selection is supposed to get rid of harmful genetic traits, why are hereditary diseases so common? Dr. Moalem says modern medicine does not really understand why many diseases appear to be wired into our genetic code and that this handicaps the medical establishment’s ability to help us lead longer and healthier lives. How might better insights into so-called Darwinian Medicine and a greater appreciation of evolutionary explanations for why people are vulnerable to various diseases improve the practice of medicine?