A dramatic fall in deaths from prostate cancer in the US has raised questions about Britain's poor performance against the commonest cancer in men.

The first evening session of the world track championships was always likely to end in a celebration of British excellence, but the enforced withdrawal of Rob Hayles after an "anomaly" in a blood test cast a shadow over the performances of Bradley Wiggins and the home sprint team in Manchester last night.

Scientists have made a major advance in understanding the genetic causes of prostate cancer, opening a new front in the battle against the most common malignant disease in men.

"I recently discovered the existence of ankylosing spondylitis (AS) while doing a web search on starch intolerance. Every time I eat starchy food the pain in my lower back, which I have had for more than 20 years, flares up. At the same time I suffer chronic cramping in my intestines. The more I read about AS, the more I am convinced it is the cause of my problems. I've been told the next stage is to see my GP to have a blood test for HLA-B27. Over the years I have often gone to my GP for bowel and back problems and I have been made to feel like a hypochondriac. Twenty years ago I was diagnosed with inflammation of the sacroiliac joint. I don't know what my GP will say if I ask for a blood test, but I imagine it will be dismissive. I've looked into a private test, but it will cost £200 and I can't afford it. What should I do?"

Brian Ashton never planned to do much in the way of training yesterday ahead of England's opening Six Nations Championship fixture with Wales this weekend, which was probably as well. Seven members of the recently expanded 33-man squad were nursing injuries – some of them of serious concern, others merely irritating – and last night the head coach and his back-room colleagues were awaiting a detailed briefing from the resident medic, Dr Simon Kemp, before settling on their line-up.

Gordon Brown promised a more personal and preventative NHS today as a new national health screening programme to provide patients with early warning of some of the biggest killer diseases was announced.

Our 15-month-old daughter has just spent two nights in a children's ward after she had a convulsion, which started when she had a cold and sore throat. She had a high temperature and then started shaking and her breathing because noisy. She was unconscious, or nearly unconscious, for a couple of minutes, before the shaking stopped and she gradually came round. We called an ambulance which arrived quickly, but by then the convulsion had stopped. She was given a blood test, but nothing was found and it was put down to a high fever it was a febrile convulsion. The whole experience was very frightening, but she does not seem to have come to any harm. However, we are now terrified that the same thing will happen the next time she develops a temperature.

I have had bouts of pain at the base of my penis for several months, and recently my semen was slightly brown in colour. Ibuprofen takes the pain away, but it comes back in a day or two. After urine tests and a rectal examination, I have been diagnosed with an infection of the prostate gland. The PSA blood test is slightly raised, but I was told this is due to infection, not cancer. What causes prostate infections? I have been put on antibiotics for eight weeks, which seems a long course. I am 38 years old and healthy, and I cycle at least 30 miles a week.

I have been to two different doctors in the past month complaining of feeling generally run-down. The second doctor listened to my heart and lungs, felt my belly, tested my urine but couldn't find anything wrong. Now I've begun to sweat heavily in bed. I work long days behind a desk, but in the evening I just want to lie down and sleep. Until a few months ago I was full of energy and up for anything. I am 35 years old, a non-smoker, and consider myself to be perfectly healthy.

"I've been having tests for anaemia, and the laboratory has discovered that I carry beta thalassaemia. I've been told that this won't cause me any problems, but my parents and grandparents were born in the UK and, as far as we know, there is no Mediterranean or Middle Eastern ancestry in our family, so how is it possible that I have this condition, which is supposed to affect only people from other parts of the world?"