Tuesday, May 16, 2017

Researchers Question Link Between Genetics and Depression

Professor Hans Eysenck said that personality was largely inherited and innate, but they had no idea of epigenetics (our genes are programmable) or neuroplasticity in those days (where our brains are modified by the environment). Eysenck wrote the book, the Inequality of Man, and told the elite that their superior genes gave them superior intelligence and that's why they did so well. The elite adored him and he was esteemed as one of the world's greatest scientists. The fact that the elite might be more crooked and ruthless than most people and that's the reason why they did so well did not come into it.

Researchers Question Link Between Genetics and Depression

A new study, published in the journal Molecular Psychiatry, found no link between genetics and the occurrence of depressive symptoms. Although previous researchers had theorized that genetics may interact with stressful life events to cause depression, the current data suggested otherwise. 
“Our findings do not support the interaction hypothesis,” the researchers write. “We found no subgroups […] for which an interaction between stress and […] genotype was statistically significant.” 
The authors suggest that research funding would be better served focusing on the known, strong causes of depression, such as life stressors and trauma, than on trying to find a genotype with an effect so small as to be undetectable in 38,000 people.
How the identical twin studies got it wrong.

Most identical twins that were said to be separated at birth weren't, they were usually separated after a few months, or even after a year. It was difficult for scientists to find twins that really were truly separated at birth because such twins usually have no idea that they have a twin sibling and so don't come forward for research.

 Reared-Apart Twin Study Mythology: The Latest Contribution (Part One), by Jay Joseph



Bob said...

Did the good professor revise his claims?

Kaivey said...

He once said that 99% off the personality was inherited. But in the post I put out thy outer day he said nurture and nature affects political views.

Tom Hickey said...

Genetics ("nature") affects what is innate as inborn. Experience and behavior ("nurture") affect what is acquired as added to what is inborn.

Sometime this is distinguished as constitution versus disposition. Constitution is innate, while disposition is a combination of innate and acquired. Constitution denotes the initial or original state, while disposition denotes state at a particular point in time.

Personality tendencies are innate, but personality can also be changed by nurture, albeit within limits. One's constitution is what one inherited while one's disposition is one's present state as a combination of innate and acquired.

I am not aware of the latest thinking but it used to be thought that the imprinting of the first three years is almost as hardwired as genetic inheritance. These can be changed through experience and behavior, but not easily. They are not malleable.

Kaivey said...

Genes are malleable. Epigenetics.

Tim Spector: Identically Different: Why You Can Change Your Genes (book)

Professor Tim Spector reveals the astonishing new science that is changing everything we thought we knew about genes and identity. 'Lucid, surprising and with a very human face. It brings epigenetics alive ... a great read!' Michael Mosley

Since the discovery of DNA, scientists have believed that genes are fixed entities that cannot be changed by environment - we inherit them, pass them on to our children and take them with us when we die.

Professor Tim Spector reveals how the latest genetic research and his own pioneering studies on epigenetics are rewriting everything we thought we knew about genes, identity and evolution. Conceptually, he explains, our genes are not fixed entities but more like plastic, able to change shape and evolve, and these changes can be passed on to future generations.

Tim Spector's dazzling guide to the hidden world of our genes reveals the complex role they play in shaping our identities, and will make you think again about everything from sexuality to religion, cancer to autism, politics to pubic hair, clones to bacteria, and what it is that makes us all so unique and quintessentially human.

Tom Hickey said...

How Mind Changes Genes through Meditation

This is just one summary article. A search brings up is a bunch of stuff on this.

Bob said...

It talks about changing the expression of genes, including activation and deactivation. What about rewriting the genome itself?