The Gene

Sharing my learnings from the book, The Gene by Siddhartha Mukherjee

The Gene by Siddhartha Mukherjee

The Gene is the story of one of the most powerful and dangerous ideas in our history from the author of The Emperor of All Maladies.

The story begins in an Augustinian abbey in 1856, and takes the reader from Darwin’s groundbreaking theory of evolution, to the horrors of Nazi eugenics, to present day and beyond – as we learn to “read” and “write” the human genome that unleashes the potential to change the fates and identities of our children. 

Majestic in its scope and ambition, The Gene provides us with a definitive account of the epic history of the quest to decipher the master-code that makes and defines humans – and paints a fascinating vision of both humanity’s past and future.

• The story of the gene begins in 1864 with Austrian botanist Gregor Johann Mendel. As part of an experiment in breeding pea plants, Mendel noticed that parent plants passed on specific traits to the next generation of pea plants intact – that is, with the traits unaltered.
• In other words, what Mendel had discovered is that hereditary information – the trait of tallness, for example – is passed down from generation to generation in indivisible units. In identifying these indivisible units, Mendel had unveiled the smallest building block of heredity, the gene. 
• Some years later Dutch botanist Hugo De Vries revived Mendel’s earlier work and was able to merge his ideas on genetics with Charles Darwin’s theory of evolution, published when Mendel was still in school. De Vries pushed Mendel’s theories further, explaining why genetic differences, or variants, occur in the first place. He discovered that such variants are accidental – freaks of nature, essentially – or as he called them, mutants. 
• DNA is the building blocks of genes; and when genes work together, traits are expressed.
• Each organism begins life as a single cell that contains its entire genetic code. When the first cell begins to divide, DNA tells each new cell which role it should play in building the new organism. This process continues as cells divide and divide again, taking on new functions. 
• Francis Galton, Charles Darwin’s cousin, coined the term eugenics in 1883. He thought human attributes like intelligence, strength and beauty could be increased in society through selective breeding. This idea led to the first court-ordered sterilization in the state of Virginia, on October 19, 1927.
• Not so long afterward, leaders in Nazi Germany took this concept to terrifying extremes. The Nazis thus distorted genetics to enact a policy of systematic sterilization. By the end of the war, the Nazis had exterminated some 11 million people. This regime showed the world how genetics could be twisted; the field of eugenics became taboo and remained so for generations.
• Stanford University biochemists Paul Berg and David Jackson found in 1970 that science create new genetic combinations in a lab. The two men successfully inserted the entire genome of a virus called SV40, together with three genes from the bacterium E. coli, into a Lambda bacteriophage. They called their new creation recombinant DNA. The process they developed would later become known as gene cloning. 
• Reading genes is precisely what gene sequencing seeks to do. The first person to successfully sequence a genome, or complete set of genes, was Cambridge-based biochemist Frederick Sanger. In 1977, he mapped all 5,386 base pairs of virus Phi X174. After this discovery, gene sequencing continued to develop, illuminating new aspects of the language of DNA. 
• Scientists found that in animal DNA, a string of base pairs are often separated by long stretches of what are called stuffer bases. These are bases that don’t appear to code for anything, but act as a space or pause between useful base “sentences.” 
• DNA sequencing can help doctors diagnose some genetic diseases, but other illnesses are still elusive.
• With the successful completion of the Human Genome Project, new doors opened in the field of genetic research. Scientists now could research every single human gene, and by comparing the genomes of people from around the world, trace the origins of the species. 
• Genes affect a person’s sex, but not necessarily a person’s gender identity
• people are born with tendencies and not traits; and it’s only when these tendencies interact with the environment that they become visible traits.
• One promising field is to find ways to cure diseases through gene therapy. Basically, scientists are exploring ways to insert genes into a sick patient to alleviate the symptoms of a disease.
• gene therapy isn’t the only promising application of advanced genetics. Stem cells are also full of genetic potential. These amazing cells can regenerate or be transformed into any other type of cell in the body. Scientists can use stem cells even to manipulate genes to build an organism from scratch. 
• Genetic manipulation seems limitless, from advanced disease diagnosis to the creation of life itself.