The Nobel laureate who discovered his sister was actually his mum

London, Dec 12 (ANI): A Nobel prize-winning geneticist who discovered that the woman whom he regarded his sister was actually his mother has now opened up about how he stumbled upon the truth.

Prof Sir Paul Nurse learnt the true nature of his genetic identity when he applied to the US Department of Homeland Security for a green card, reports the Daily Mail.

Currently the president of the Royal Society, Britain, Nurse was more intrigued by the quirks of his genetic makeup than most all his life.

So when he discovered by chance three years ago that he had been deceived about his true genetic identity, the irony was not lost on him.

"I've always been interested in my own genetic make-up because I was always the odd one out in my family. But even though I'm an expert my family managed to keep my genetic origins secret from me for over half a century," he said.

"The people I thought were my parents weren't my parents at all," he added.

The revelation came when Sir Paul, now 61, applied for a green card, which would allow him permanent residence in the US.

At that time he had been living in the US for three years and was president of New York's Rockefeller University, so when his application was turned down he was surprised.

He was told there was a problem with the short-form version of his birth certificate, which did not contain the names of his parents, so he applied for a fuller version.

"When it arrived my secretary asked me if I'd made a mistake with my mother's name. I said, 'Of course not'," said the gene genius.

She handed it to me and for the next few seconds I was totally dumbstruck," he said.

"I saw that next to the word 'mother' was my sister Miriam's name, and next to 'father' was just a dash. I didn't believe it at first: I assumed it was a bureaucratic mix-up,' he added.

" I couldn't ask my mother about it as she died a long time ago and my sister died early, too, of multiple sclerosis. Eventually though, I noticed that the birth certificate said I was born in my great-aunt's house in Norwich, so I rang her daughter, who told me it was true: the woman I'd always known as my sister was my mother and my 'parents' were my grandparents," said Sir Paul. (ANI)