Book Review - The Gene: An Intimate History

In The Gene: An Intimate History, the oncologist-author Siddhartha Mukherjee amazed me with his passionately compelling and masterful storytelling of genes and genetics just like he did with his earlier award-winning book The Emperor of All Maladies: A Biography of Cancer

Mixing science and history in an engaging way, the book offers a new multidimensional  perspective to appreciate otherwise dry academic topics.  It provides simple answers through explanations that are relatable and accessible even to non-scientists. It tells the inspiring stories of legendary scientists (like Mendel) who failed to achieve conventional milestones of success but marched on nevertheless. It was a discovery to me that Gregor Johann Mendel who is considered "the father of modern genetics" achieved that recognition posthumously - three decades after he passed away! He is now on the top of my list of science heroes!

Paraphrased notes and excerpts:

It is a testament to the ability of scientists to accept abstractions as truths that fifty years after the publication of Mendel’s paper—from 1865 to 1915—biologists knew genes only through the properties they produced: genes specified traits; genes could become mutated and thereby specify alternative traits; and genes tended to be chemically or physically linked to each other. Dimly, as if through a veil, geneticists were beginning to visualize patterns and themes: threads, strings, maps, crossings, broken and unbroken lines, chromosomes that carried information in a coded and compressed form.

In 1911, Alfred Sturtevant, a 21 year old undergraduate student in Thomas Morgan's lab called the Fly Room, sketched the first linear genetic map of half a dozen genes along a Drosophila (fruit fly) chromosome laying the foundation for the Human Genome Project. Over the next decades, a spray of Nobel Prizes would be showered on the occupants of the Fly Room for their discoveries.

Hemophilia is a genetic illness caused by a single mutation that disables a protein in the clotting of blood.

When an organism reproduces, it transmits the instructions to build embryos, make cells function, enable metabolism....and produce future organisms of the same species - all in one grand, unified gesture.

Genes move in packs physically carried on chromosomes. Y chromosomes determine maleness

In humans, a mutant BRCA1 gene increases the risk for breast cancer— but not all women carrying the BRCA1 mutation develop cancer.

We still do not know what causes the difference of outcomes ...but it is some combination of age, exposures, other genes, and bad luck.

genotype + environment + triggers + chance = phenotype

A genotype is an organism's genetic composition. It can refer to one gene, a configuration of genes, or even an entire genome

A phenotype, in contrast, refers to an organism's physical or biological attributes and characteristics—the color of an eye, the shape of a wing, or resistance to hot or cold temperatures.

Tired of mutant hunting, Hermann Muller wondered if he could accelerate the production of mutants—perhaps by exposing flies to heat or light or higher bursts of energy...In the winter of 1926, acting on a whim, he exposed a cohort of flies to an even lower dose of radiation. It had taken nearly three decades for Thomas Morgan and his students to collect about fifty fly mutants in New York...Muller had discovered nearly half that number in a single night. Muller also realized that his experiment had broad implications for human eugenics. If fly genes could be altered with such modest doses of radiation, then could the alteration of human genes be far behind? If genetic alterations could be “induced artificially,” he wrote, then heredity could no longer be considered the unique privilege of an “unreachable god playing pranks on us.”

Nazism, the biologist Fritz Lenz once said, is nothing more than “applied biology.”

In 1936, the University of Munich, an institution richly endowed by Hitler, awarded a PhD to a young medical researcher for his thesis concerning the “racial morphology” of the human jaw—an attempt to prove that the anatomy of the jaw was racially determined and genetically inherited. The newly minted “human geneticist,” Josef Mengele, would soon rise to become the most epically perverse of Nazi researchers, whose experiments on prisoners would earn him the title Angel of Death.

Identical twins are derived from the splitting of a single fertilized egg, thereby resulting in twins with identical genomes, while fraternal twins are derived from the simultaneous fertilization of two eggs by two sperm, thereby resulting in twins with nonidentical genomes

Morbidly interested in genetics and medical research, Josef Mengele (the anthropologist-turned-physician-turned-SS-officer) rose to become physician in chief at Auschwitz, where he unleashed a series of monstrous experiments on twins. Despite the ersatz patina of science, Mengele’s work was of the poorest scientific quality.

Germany had dominated science in the early twentieth century: it had been the crucible of atomic physics, quantum mechanics, nuclear chemistry, physiology, and biochemistry. Of the one hundred Nobel Prizes awarded in physics, chemistry, and medicine between 1901 and 1932, thirty-three were awarded to German scientists (the British received eighteen; the Americans only six). 

Like musicians, like mathematicians—like elite athletes—scientists peak early and dwindle fast. It isn’t creativity that fades, but stamina: science is an endurance sport. To produce that single illuminating experiment, a thousand non-illuminating experiments have to be sent into the trash; it is battle between nature and nerve.