The Gene An Intimate History is an moving account of the discovery and development of genetics, the science of inheritance and chemical basis that give living things their forms and functions. The book is also the author’s deeply personal story of how genetics linked diceases burdened his larger family.

Within a century time, genetics has gone from non-existence to one of mankind’s greatest endeavor to understand nature and ourselves. At the beginning of 20th century, Mendel’s theory was re-discovered, which stated that there exist a concrete indivisible unit of inheritance that got passed on from parents to offsprings. Physical traits from parents re-emerge in children distinctively rather than average out. E.g cross breeding a white flower plant with a red one would result in either white or red color plants, not pink one. And then, when scientists discovered that human’s genome resides on 23 pairs of chromosomes, gene had taken its material form, no longer an abstract theory. After that, Watson and Crick discovered the chemical structure of gene as double helix DNA molecules. At the end of the 20th century, thousands of researchers joined effort to sequence the human’s genome, a project as iconic of the century as landing people on the moon.

The human’s genome is approximately 3 billions of DNA bases (A, G, T , C). Visually speaking, printing thoses bases double sidedly on an A4 paper, it would take a million pages to contain it all. And the book provides a number of delightful details about our own genome. Number of genes that constitute the human genome is fewer than that of rices and corns. Nature has a way to make more with less. It achieves complexity not with more materials but rather with more intricate arrangment of those materials. Besides, throughout the human’s genome, we share many common genes with fruit flies, worms. Million years of evolution still leave traces behind. Those genes stay dormant in our genome, inactive but unable to leave.

As mankind’s understanding of genes evolved, one thing has remained constant: human’s aspiration to be better and to be closer to perfection. That desire at time led to horrors like the eugenic movement, which arrogantly proposed to get rid of bad genes. Thousands of people that were deemed imbecile, dim-witted were put in concentration camp, isolated, sterilized. Cruel and confusing time it was. Judging the quality of genes from subjective measurement like intelligence is absurd and prone to abuse. Under Nazi German, eugenics escalated to exterminating cripples, homosexuals, and Jews. Nowaday, genetic technologies have allowed researchers to tamper with human’s DNA first to cure disceases. Many have in sight the goal of engineering a better human, not limited by what have been shown to us by nature. A Netflix documentary, Unnatural Selection, shows that so-called biohackers are already distributing DIY DNA kits with which brave souls can start altering themselves right now.

One thing to note is that, as Victor McKusick has realized when documenting various genetics linked diceases, there are no normalcy in genes, just variations. What we call diceases are more about the relationship between a genetic variation and its environment, whether it helps or hinders the organism’s survival. Genetic variations are human kind’s pool of resources to draw on in time of environmental shifts, and the condition necessary for Darwinian evolution to work. That is to say, there will be inherient risk in trying to engineering our DNA to perfection, which would deprive nature of its needed gene pool.

The last century was about building the foundation of genetics. This century, building on that foundation together with advancements in computers and AI, genetics will surely move much faster. Who knows which path genetics will lead us down in this century. For better or worse, we should expect radical changes in how we deal with diceases, our sense of selves, our view of morality, equality.