Modern Genetics Quotes

When scientists underestimate complexity, they fall prey to the perils of unintended consequences. The parables of such scientific overreach are well-known: foreign animals, introduced to control pests, become pests in their own right; the raising of smokestacks, meant to alleviate urban pollution, releases particulate effluents higher in the air and exacerbates pollution; stimulating blood formation, meant to prevent heart attacks, thickens the blood and results in an increased risk of blood clots in the heart. But when nonscientists overestimate [italicized, sic] complexity- 'No one can possibly crack this [italicized, sic] code" - they fall into the trap of unanticipated consequences. In the early 1950s , a common trope among some biologists was that the genetic code would be so context dependent- so utterly determined by a particular cell in a particular organism and so horribly convoluted- that deciphering it would be impossible. The truth turned out to be quite the opposite: just one molecule carries the code, and just one code pervades the biological world. If we know the code, we can intentionally alter it in organisms, and ultimately in humans. Similarly, in the 1960s, many doubted that gene-cloning technologies could so easily shuttle genes between species. by 1980, making a mammalian protein in a bacterial cell, or a bacterial protein in a mammalian cell, was not just feasible, it was in Berg's words, rather "ridiculously simple." Species were specious. "Being natural" was often "just a pose.

Siddhartha Mukherjee

McKusick's belief in this paradigm-the focus on disability rather than abnormalcy-was actualized in the treatment of patients in his clinic. Patients with dwarfism, for instance, were treated by an interdisciplinary team of genetic counselors, neurologists, orthopedic surgeons, nurses, and psychiatrists trained to focus on specific disabilities of persons with short stature. Surgical interventions were reserved to correct specific deformities as they arose. The goal was not to restore "normalcy"-but vitality, joy, and function. McKusic had rediscovered the founding principles of modern genetics in the realm of human pathology. In humans as in wild flies, genetic variations abounded. Here too genetic variants, environments, and gene-environment interactions ultimately collaborated to cause phenotypes-except in this case, the "phenotype" in question was disease. Here too some genes had partial penetrance and widely variable expressivity. One gene could cause many diseases, and one disease could be caused by many genes. And here too "fitness" could not be judged in absolutes. Rather the lack of fitness-illness [italicized, sic] in colloquial terms- was defined by the relative mismatch between an organism and environment.

Siddhartha Mukherjee