ALL MEN ARE NOT CREATED EQUAL

Alasdair Palmer talks to the man hunting

for the genes which determine human intelligence, and explains why his work is so feared and detested

The conclusion that genes shape behaviour is about as resolutely politically incorrect a view as you can get. Politically correct scientists resist it as hard as any other group. The June edition of Scientific American spends nearly ten pages trying to debunk 'behavioural genetics', raising in particular a number of doubts about the quality of the work on identical twins which has produced such startling evidence for the genetic view. Thomas Brouchard, the psychologist behind the most important of the twin studies, answered Scientific Ameri- can's criticisms point by point in correspon- dence before the article was published. Not one of his points was mentioned in what Scientific American finally published. Instead, Brouchard's detractors, who deny genes have any role in behaviour, were uncritically reported. As a result, the scien- tific community's most prestigious general magazine gave the impression that geneti- cists were dogmatists ignoring evidence, whilst researchers adopting the PC line that environment can explain everything were rational, cautious scientists taking account of the facts.

In fact, the opposite is much closer to the truth. But no one is eager to recognise the extent to which genes dictate what we are and what we can become. The power of genes, however, will become progressively harder to deny as the Human Genome Project nears completion.

Whilst insurance companies and employ- ers will probably kill to get their hands on those details, many ordinary citizens might prefer not to know: ignorance at least allows hope. Knowledge can destroy it.

`Some of the genes related to IQ will be discovered by the turn of the century. I'd bet my house on that. If we're lucky, we may isolate half of those responsible for individual variations.' Professor Robert Plomin, the man who is currently responsi- ble for the search for those genes, is quietly confident of success, despite the technical problems involved in tracking them. 'It won't be like sickle cell anaemia or cystic fibrosis. There won't be a single gene that controls intelligence. There'll be a cluster of them. It may be scores, or it may be thousands, each of which makes a small difference. Nobody is quite sure yet.'

But they are quite sure that a large por- tion of intelligence is genetically deter- mined. IQ has long been recognised as one of the most heritable characteristics. The best way to predict your IQ is to average the IQ of your biological parents. That pre- diction — which has been formulated and refined within the appropriate statistical limits — holds regardless of whether your biological parents bring you up, or give you away to be raised in a totally different home without any further contact with them. The result is probably the most important one in the behavioural or social sciences. Certainly it's the only one which has proved to have any predictive power.

Studies of twins separated at birth indi- cate that between 50 and 70 per cent of the variation in IQ scores in a given population is due to genes. That means that if my child has an IQ of 100 and yours has one of 120, my child will never be able to reach your kid's score. The gap between the two will always be between ten and fourteen points. You may"Want everyone to know about your offspring's superiority, but I'm not sure I'd want anyone to know the truth about mine. Educational achievement, income, socio-economic status — the usual measures of success — all cotrelate with IQ scores. Not perfectly, but well enough for a low IQ score to be by far the best pre- dictor we have of a low-income, low-status, low-achieving life. Would anyone want their child to start off in a world where everyone would be able to predict that his intelligence was genetically inferior?

It is not merely the fact of the heritability of intelligence that is alarming. It is the dis- covery and refinement of all the details relating to it. If Professor Plomin's research is successful, geneticists may be able to predict IQ scores by taking a single cell from an embryo. 'That's possible, but not imminent,' he cautions. 'It will be years before anyone is able to better a prediction based on the average of the parents' scores.' But it may happen sooner than he thinks. Even if it was only possible to pre- dict between 20 and 40 per cent of the dif- ference in intelligence between different embryos, that would provide many parents with a reason for selective abortion. (Dar- ling, I've just heard that this year's preg- nancy suggests an IQ of under 100. We'll have to abort it . . .') In vitro fertilisation also allows parents to choose between dif- ferent embryos. The potential people those embryos represent could be as different as brothers and sisters within any family. Ranking them by their genes for intelli- gence would give their parents a criterion by which to choose which embryo to implant. And where parents have the money, doctors and geneticists will be found to perform the necessary tricks.

Professor Plomin is in no doubt that selective abortion (or implantation) of that kind would be an abuse of his work. He would rather concentrate on its potential benefits: as the genes for intelligence are also the genes for mild mental handicap, it may be possible, once he has isolated those genes, to find ways of alleviating or even eliminating that form of disability.

Still, work in the genetics of intelligence seems constantly to challenge the Enlight- enment assumption that knowledge is always better than ignorance. The entire scientific establishment seems to feel deeply queazy about the whole enterprise. Of the thousands of geneticists associated in one way or another with the Human Genome Project, Professor Plomin is the only one working on finding the genes for intelligence. Only five years ago he could not find anyone who would fund his research. 'The committees just laughed the idea off their lists of approved topics.' Now he has a grant for $800,000 from the National Institute of Child Health and Human Development. It's peanuts in com- parison to the multi-millions going to the teams of researchers working to isolate genes for less controversial human attributes. The project to isolate the gene for alcoholism, for example, landed a $25 million grant, even though there is not much evidence that the disposition to swill vodka or guzzle beer and wine indiscrimi- nately is actually heritable.

`All men are created equal,' states the American Declaration of Independence, a truth 'we hold to be self-evident'. That belief is built into the ideology of all liberal capital democracies. Plomin's work is so controversial because it attacks it. Before the genes which dictate variations in intel- lectual potential are isolated, it will always be possible to hope that there is some hid- den environmental factor which explains them. Locating those genes will smother that hope. We shall be stuck with the con- clusion that there are very definite limits to what can be done to equalise differences between individuals.

As Professor Plomin puts it, 'The more you equalise the environments, the more the remaining differences between individ- uals — and of course there are and will be c-i5014 1 Tin sorry, gentlemen. There's no TV in Heaven. That's to be had in Hell. It's compulsory there.'

large variations — will be genetic in origin.' Suppose we were all born and raised in identical social and family environments. Genetic factors would then be responsible for 100 per cent of the differences that existed between individuals in intelligence, rather than for 50 to 70 per cent of the variation accepted today. So, in one sense, the more we try to make social environ- ments equal, the more we'll guarantee an unequal outcome.

That fact rules out one form of egalitari- an utopia — and with it a great deal of egalitarian idealism. That is why there is so much resistance to the discovery that dif- ferences in intelligence are in large part genetic. When the American educational psychologist Arthur Jensen first proposed the idea in an article for the Harvard Edu- cational Review over 20 years ago, the explosion of protest nearly ended his career. He was called a fascist, a Nazi, a fraud, an ignoramus and a cretin. He even received regular death threats. The same things happened to Hans Eysenck when he developed Jensen's ideas in Britain: stu- dents at the LSE smashed his glasses and tried to beat him up. Eysenck — a German Jew, and a refugee from Nazism — found that everywhere he went he was accused of being a supporter of Hitler. But Jensen and Eysenck are now recognised to have been right, at least by people who work in the psychology of intelligence.

Of course, Jensen did not help the accep- tance of the heritability of intelligence by attaching to it an explicitly racial — every- one called it racist — component. He looked at the fact that black Americans consistently score between 15 and 20 points lower than whites on IQ tests, and conclud- ed that it was not unreasonable to assume that the difference was genetic. 'That almost put an end to genetic research into intelligence,' Professor Plomin told me. `No one wanted to fund it, and no one wanted to do it.' They still don't. Plomin's is a lone quest because almost everyone else was scared off the topic, partly by what happened to Jensen, and partly because they just do not want to find out the truth in this area. Plomin himself is not going to touch the race issue. 'But there are good scientific reasons for that,' he explained. `Quantitative genetics is about individuals and differences between them. It is almost impossible to study average differences between races.'

Others would rather censor what results there are on racial differences in IQ. For instance, Paul Kline, Professor of Psycho- metrics at Exeter, in his recent book Intelli- gence: The Psychometric View mentions Jensen's work and then explains why he would not even report Jensen's results. Professor Kline's reasons are utterly com- prehensible — a wish 'not to sacrifice the humanness of the person in the interests of objective truth' — but they are a counsel of despair, and represent a terrible defeat for the hope that the relentless pursuit of truth

can only be a force for good.

That hope has shaped scientific activity since Galileo whispered, 'But it does move,' as the Catholic Church bullied him into recanting his views on the motion of the earth. It also explains why liberal democracies still believe in promoting free inquiry, rather than doing their best to sup- press it — as did the mediaeval Catholic Church. But work on the genetics of intelli- gence can seem as threatening to a liberal, egalitarian outlook as displacing the earth from the centre of the universe was to the 17th-century popes.

What consequences the slow but sure discovery of the genes dictating intelligence will have for political policy is very unclear. At one end of the spectrum there is the hideous spectre of state-sponsored eugen- ics. That was very popular before the war, and not only in Nazi Germany. Britain's Eugenics Society used regularly to recom- mend the elimination of 'the family stock which produces paupers, the feeble-mind- ed, alcoholics and certain types of crimi- nals'. In America, the city of Chicago drafted a 'model law for the sterilisation of the socially inadequate . . . and the poten- tial parents of socially inadequate off- spring, who would carry the genes for one or more inferior or degenerate psychologi- cal qualities'.

At the other end of the spectrum, there is the possibility that large efforts will be made to compensate the genetically disad- vantaged. There aren't any historical prece- dents for that — which may indicate how likely it is to come about. The closest any society has come to it is the positive dis- crimination programmes in the United States. But the rationale behind those has very firmly depended on the view that any educational failing on the part of a disad- vantaged group — blacks, or women, or whoever — is due to environment: a deprived social background, or prejudice, or both, is to blame. Take away those, argue the advocates of 'positive discrimina- tion', and the group concerned would have performed as well, or better, than any other. But how can that conviction survive the discovery that the cause of relative edu- cational failure is in large part genetic? No wonder most who hope for the continua- tion of a liberal, egalitarian society are doing their best to ignore, deny or bury results about the genetics of intelligence. As one psychiatrist who gave up his work in the area said to me, 'I wondered what I would say to my grandchildren if they asked me why I had done this kind of work. Hadn't I stopped to think about the conse- quences? It didn't seem an adequate answer to say, "Well, it looked very inter- esting and I got the proposal through the ethics committee . .

But turning away is not a strategy we, as a society, can adopt. Sooner or later, a large set of uncomfortable facts is going to have to be confronted. The genie is now out of the bottle.