Taking a sample from one part of a tumour may not reveal its full genetic identity, according to research by scientists from Cancer Research UK (CRUK).

BBC: DNA analysis shows huge genetic diversity in tumours

Dr Brennan, who was the clinical director of the service from October 1990 until he took paid leave in June 1997, failed to carry out a key test on dozens of women which involves taking a sample of cells from the suspected cancer with a fine needle, the GMC was told.

BBC: Doctors 'failed breast cancer patients'

Instead of taking the temperature of a representative sample of customers, firms must identify the few special customers who innovate.

ECONOMIST: The future of innovation

Another experiment the team are carrying out involves taking a metre-deep soil sample, which co-researcher Rebecca Rowe describes as "quite unusual".

BBC: Measuring bioenergy crops' carbon footprint credentials

His approach involves taking a muscle biopsy from a patient's thigh and then growing the tissue sample in the lab for three weeks until there are 600 million to 800 million of the myoblast cells.

FORBES: Using Thigh Muscle To Fix The Heart

In truth, though, this is hardly a representative sample, since the exhibitionists taking part are goaded on by the presence of the cameras.

ECONOMIST: We love you, Big Brother

"Vica versa it's really helped as well, " he says, explaining that he is currently taking a class in e-commerce in which students usually have to use invented sample business data.

CNN: The MBA entrepreneurs