Peter York On Ads

DNA testing has knocked the nature-vs-nurture question sideways. Even Seventies sociologists acknowledge that you can "have the gene" for something – a characteristic, a condition. So what sounds like genetic determinism – a tricky subject for obvious reasons, and deeply unfashionable until the new science emerged – is becoming more influential in shaping policies and attitudes. The old approach – long, speculative studies of identical and fraternal twins, with controls for the effects of family and peer group, class and ethnicity – seems clonky and dated.

Now we feel we know: it's all science, really. It would certainly make things simpler, if more brutal, and politically even harder, if it were 99 per cent nature. It would let rich meritocrats off the hook, for instance, if they felt "losers" were inherently hopeless, offenders inherently wicked. On that basis, within a generation, there'd be no conscience of the rich.

But the answer to the simplistic "it's all in the genes/talent will out" view comes in the mass of evidence that it doesn't seem to be working out at all like that in modern Britain. The return to stable, middle-class backgrounds, private schooling, careful coaching and all the "environmental" advantages seems to be gathering pace. Access to good universities, "nice" jobs and highly paid ones goes quite disproportionately to lucky children.

And first-generation meritocrats spend time and money making sure their children get some hard-wired advantages. They don't just trust to their DNA. It was one of the major embarrassments of the Blair years that Britain grew steadily more polarised on so many indices. Was it something he or Peter Mandelson said (as in, "We're intensely relaxed about people getting filthy rich"), or something about the world needing more educated people? Whatever it was, the thrust of Babyboomer social mobility seemed to be over.

And all that polarisation, post-Thatcher, seemed so much more dramatic when the new visible super-rich arrived locally, then globally, in such numbers.

The DNA discoveries about, say, the predisposition to Alzheimer's are pretty convincing, but so is the statistical evidence about life chances. It really is about how they work together. Health, diet and other factors can all mitigate genetic likelihoods.

Inheritance is the theme of the new anti-smoking commercial put out by the Central Office of Information. It starts amusingly enough, without any clue to the client. It could be a DIY retailer or an online encyclopedia. A mass of cute kids are copying their parents doing all sorts of useful things. Little girls imitate their mothers in the kitchen or dress up from their wardrobes. They push dolls' prams and put on make-up. Boys do exercises, fix cars or pretend to shave. And they do it to the sound of the song "I Wanna Be Like You" from 'The Jungle Book', one of the most commercially successful children's films ever, an instant cue to several generations of mothers who have bought it on video and DVD.

But the final frames show a rather desperate-looking mother smoking and, as the music fades, her daughter imitating her with a crayon. "If you smoke, your children are more likely to," they say. "Don't keep it in the family."

But what kind of inheritance are they talking about? Is there really a smoking gene, or is this a mother from the social world of Waynetta Slob and Vicky Pollard, where everyone's always got a fag on?