Sir

In response to recent press coverage of advances in genetics, you are quick to point out the imagined political and social dangers of a belief in biological determinism, citing Nazi Germany as a precedent (Nature 387, 743;743; 1997).

Perhaps you could explain to your readers why similar comments, quoting the vastly greater number of people who perished at the hands of regimes committed to the dogma of cultural determinism in the Soviet Union, China, Cambodia and elsewhere, are never made. Why is it that the death of millions of Jews is routinely hung around the neck of genetics, while that of millions more belonging to many different ethnic and social groups is never laid at the door of the sociological theories that were used to justify their persecution — particularly when such theories are still widely taught and credited?

Surely, if doctrines were to have health warnings attached to them objectively assessed by the number of individuals they had harmed, the fashionable Marxist belief that the social environment is much more important than anything else would be rated many times more harmful than any acknowledgement of the influence of genes.

As you say, knowledge is power, but the power to kill millions during our century has come much more from the belief that human beings are the hapless victims of ‘ideology’, ‘society’ or ‘class’ than it has from any knowledge of genetics, however faulty or misapplied it may have been. Your leading article eloquently reveals the extent to which everyone is now acutely aware of the dangers of misapplied genetic knowledge. The real worry is that there is much less awareness of the potentially greater dangers of credulity for doctrines of social-determinism.