On Genome

I have recently read Genome – The Autobiography of a Species in 23 Chapters by Matt Ridley. I picked up this book based on a recommendation by business magnate Charlie Munger. As the author best summarizes: “An in-depth analysis of genes in a simple language. The story of Human Genome project in 23 chapters, each dedicated to a chromosome. Each chapter brings out a specific gene on a chromosome to bring out a remarkable history of all living things.”

Below are selected excerpts from the book that I found particularly insightful:

Complex biological organs can be reverse-engineered to discern what they are ‘designed’ to do, in just the same way that sophisticated machines can be so studied.

The idea of genes in conflict with each other, the notion of the genome as a sort of battlefield between parental genes and childhood genes, or between male genes and female genes, is a little-known story outside a small group of evolutionary biologists. Yet it has profoundly shaken the philosophical foundations of biology.

Variation is an inherent and integral part of the human— or indeed any – genome.

Some time in the 1970s, as happened in physics half a century before, the old world of certainty, stability and determinism in biology fell . In its place we must build a world of fluctuation, change and unpredictability. The genome that we decipher in this generation is but a snapshot of an ever-changing document. There is no definitive edition.

There is a far greater fallacy that we all commit, so easily that we never even notice it. We instinctively assume that bodily biochemistry is cause whereas behaviour is effect, an assumption we have taken to a ridiculous extent in considering the impact of genes upon our lives. If genes are involved in behaviour then it is they that are the cause and they that are deemed immutable. This is a mistake made not just by genetic determinists, but by their vociferous opponents, the people who say behaviour is ‘not in the genes’

The psychological precedes the physical. The mind drives the body, which drives the genome.

Social behaviour is not some external series of events that takes our minds and bodies by surprise. It is an intimate part of our make-up, and our genes are programmed not only to produce social behaviour, but to respond to it as well.

Each species , it seems, comes equipped with a program of planned obsolescence chosen to suit its expected life-span and the age at which it is likely to have finished breeding . Natural selection carefully weeds out all genes that might allow damage to the body before or during reproduction. It does so by killing or lowering the reproductive success of all individuals that express such genes in youth. All the rest reproduce. But natural selection cannot weed out genes that damage the body in post-reproductive old age, because there is no reproduction of the successful in old age.

Paternal genes , inherited from the father, are responsible for making the placenta; maternal genes, inherited from the mother, are responsible for making the greater part of the embryo, especially its head and brain.

The evidence from zoology has always pointed that way: male behaviour is systematically different from female behaviour in most species and the difference has an innate component. The brain is an organ with innate gender. The evidence from the genome, from imprinted genes and genes for sex-linked behaviours, now points to the same conclusion.

The Baldwin effect is about the delicate balance between cultural and genetic evolution. They are not opposites, but comrades, trading influence with each other to get best results.

When you learn something, you alter the physical network of your brain so as to create new, tight connections where there were none or weaker ones before.

More conventional scientists were reluctant to accept that cancer was a genetic disease: after all, except in rare cases, cancer was not inherited. What they were forgetting was that genes are not confined to the germline; they also function during an organism’s lifetime in every other organ.

The longer we live, the more mistakes we accumulate in our genes, and the greater the chance that an oncogene may be jammed on and three tumour-suppressor genes jammed off in the same cell.

Genetic diagnosis followed by conventional cure is probably the genome’s greatest boon to medicine.

This brief history of eugenics leads me to one firm conclusion. What is wrong with eugenics is not the science, but the coercion. Eugenics is like any other programme that puts the social benefit before the individual’s rights. It is a humanitarian, not a scientific crime.

Many modern accounts of the history of eugenics present it as an example of the dangers of letting science, genetics especially, out of control. It is much more an example of the danger of letting government out of control.

Everybody’s fate is determined, but by their controlled environment, not their genes. It is indeed biological determinism, but not genetic determinism.

Do you begin to see why I facetiously flirted with the idea of a gene for free will? A gene for free will would not be such a paradox because it would locate the source of our behaviour inside us, where others cannot get at it. Of course, there is no single gene, but instead there is something infinitely more uplifting and magnificent: a whole human nature, flexibly preordained in our chromosomes and idiosyncratic to each of us. Everybody has a unique and different, endogenous nature. A self.

A highly recommended read in the area of biology and genetics.


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