Be more dialectical

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I was surprised to read such an uncritical review by Kevin Devine of Oliver James’s book Not in Your Genes (June SR).

Discussing mental health, James argues that “what is crucial is how, as children, we are (or aren’t) nurtured by our parents”. It is true that family tensions can have a negative impact on mental health.

But to reduce the situation to one in which “children are born with brains of soft clay, their mental makeup unaffected by genes and infinitely mouldable by their parents”, as University of Edinburgh psychologist Stuart Ritchie has described James’s viewpoint, is not only scientifically incorrect, but can lead to parents becoming the primary targets of blame for their children’s poor mental health.

The evidence points to mental disorders being the consequence of a subtle interaction between social and biological factors.

The more we learn about the biological basis of mental conditions such as depression, bipolar disorder, schizophrenia or autism, the more it becomes clear that there is no simple genetic determinism, as is the case for single-gene disorders like the lung disease cystic fibrosis, or the premature dementia characteristic of Huntington’s chorea.

That is not to say that there is no genetic link at all, as James argues in his book. Instead, increasing evidence points to a situation in which genetic differences have a role to play, but only subtly, in certain social circumstances.

For instance, a recent study has found that individuals with a change in one of the regions of the genome that acts to switch on a gene called AKT, are more likely to succumb to schizophrenia, but only if they also smoke excessive amounts of cannabis as teenagers.

Another study found that certain nine year old boys who had been subjected to extremely stressful home environments as toddlers had significantly altered telomeres — the structures that protect the ends of chromosomes from damage.

This is important because telomere shortening has been linked to susceptibility to disease, and to premature ageing. But this was only true of a few boys with a genetic difference in a gene linked to the stress response.

Intriguingly, the same genetic difference in boys who had a nurturing, caring home environment, had telomeres that were longer than normal. This shows that there is no simple relationship between a genetic difference and its effects in different environments, exactly what a dialectical approach to biology would predict.

Instead of the two poles of biological and social reductionism, only a dialectical viewpoint can fully appreciate that human characteristics and disorders are the product of both biology but also society, not only the home environment, but also wider society.