The research at the centre of the row over GM food safety was conducted at the Rowett Research Institute in Aberdeen by the Hungarian-born scientist, Dr Arpad Pusztai. Dr Pusztai is recognised as the world's leading expert on the protein, lectin.
Dr Pusztai (68) was suspended from the Rowett Institute last August after appearing on Granada Television's World in Action, on a programme called Eat Up Your Genes.
In it he described preliminary results from tests in which he fed rats on genetically-modified potatoes containing genes from the snowdrop and the jackbean. These genes produce lectin, which protect the potato plants from pests.
The tests lasted for more than 100 days. Dr Pusztai said the rats fed on the modified potatoes were smaller and less resistant to infection than those which were fed on unmodified potatoes. Their bodily organs, including their heart, liver and brain, were also smaller, and their stomachs were damaged.
The tests had been publicly funded with £1.6 million from the Scottish Office. The objective was to determine whether modified foods could cause harmful effects on the rats.
During the programme, Dr Pusztai declared he would not eat modified crops until more trials had been carried out.
Dr Pusztai was given permission by the Rowett Institute to appear on the programme, but he was suspended afterwards and then ordered to retire. The institute claimed he had presented "misleading information" on research that had not yet been properly analysed.
Lectin is a known poisonous substance and the potatoes fed to the rats contained high levels of lectin.
The head of the Rowett Institute, Prof Philip James, who ordered Dr Pusztai's suspension, yesterday defended his decision and said he was mystified by the claims of the scientists who were now supporting him.
"I am not embarrassed. I am intrigued as to what they have seen that I haven't had the opportunity of looking at," he told BBC Radio 4's World at One programme.