Letter: I should be dead

Sir: OK, so why haven't I mutated? ("Passive smoking in pregnancy causes gene mutation in babies", 29 September.)

I and my three siblings, like most of our generation, grew up with chain- smoking parents, and every public building we went into was permeated with tobacco smoke. All our water came through lead pipes, our rooms were heated with smoky coal fires and lit - in the earliest days - by gas lamps. Winter was a succession of smogs. Our bread was white - the more refined the better - our diet heavily into fat, starch and sugar, and during the war-time years fruit was a rare luxury.

According to the pieces of research (usually from America) you so often publish, we should have been obese brain-damaged morons, riddled with cancer and choking to death by our tenth birthdays. We are now in our seventh and eighth decades and, except for a late-developed case of MS, we are all in good shape and good health. What went wrong?

MARGARET DUGGAN

London SW11