I just wanted to thank you' he says, his voice low. 'A group of scientists told you that my genes were damaged, that there was something wrong with me - they showed you the test results that proved it. And even I started to believe it.' He touches my face, his thumb skimming my cheekbone, and his eyes are on mine, intense and insistent. 'You never believed it,' he says 'Not for a second. You always insisted I was... I don't know, whole.
The brain is heavily influenced by genes. But from birth through young adulthood, the part of the human brain that most defines us (frontal cortex) is less a product of the genes with which you started life than of what life has thrown at you. Because it is the least constrained by genes and most sculpted by experience. This must be so, to be the supremely complex social species that we are. Ironically, it seems that the genetic program of human brain development has evolved to, as much as possible, free the frontal cortext from genes.
Stress can alter the expression of genes, which can affect the response to stress and so on. Human behavior is therefore unpredictable in the short term, but broadly predictable in the long term.
The strange fact that out of millions of people in the world, your mother and father met and decided to get married to each other. And out of the millions of sperm, that the one with your genes was the one that made it to the egg and fertilised the egg. I'll never forget it.
TP53 seems to encode the greater good, like a suicide pill in the mouth of a soldier that dissolves only when it detects evidence that he is about to mutiny.
The brain is heavily influenced by genes. But from birth through young adulthood, the part of the human brain that most defines us is less a product of the genes with which you started life than of what life has thrown at you. Because it is the last to mature, by definition the frontal cortex is the brain region least constrained by genes and most sculpted by experience. This must be so, to be the supremely complex social species that we are. Ironically, it seems that the genetic program of human brain development has evolved to, as much as possible, free the frontal cortex from genes.