Mona Lisa mystery: Is da Vinci painting of bearded man?

The Mona Lisa's mysterious smile may hide an uncomfortable secret - that she's really a bearded MAN.

Some scientists believe the world's most famous painting could be a disguised self-portrait of artist Leonardo da Vinci.

And now they want to test their amazing theory by getting permission to exhume the remains of Leonardo and study his skull.

Anthropologist Giorgio Gruppioni said the project could throw new light on Leonardo's famed work, explaining: "If we find his skull, we could rebuild Leonardo's face and compare it with the Mona Lisa."

The identity of the Mona Lisa has been debated for centuries, with speculation ranging from Leonardo's mother to Lisa Gherardini, the wife of a Florentine merchant.

Some scholars have suggested that Leonardo's presumed homosexuality and love of riddles led him to paint himself as a woman.

American expert Lillian Schwartz drew on computer studies to highlight apparent similarities between the features of the Mona Lisa and those of a self-portrait by the artist. A team from Italy's National Committee for Cultural Heritage , a leading association of scientists and art historians, has now asked to open his tomb.

The Renaissance painter is buried at Amboise castle, in France's Loire valley, where he died in 1519, aged 67.

After talks with French cultural officials and the owners of the chateau the Italians hope to receive the go-ahead this summer.

Silvano Vincenti, head of the team, said its first step would be to verify the remains are those of Leonardo by using carbon dating and comparing DNA from the bones with that from known relatives.

The tests could also reveal if he died of a disease such as syphilis or tuberculosis.

Bone tests may also establish whether Leonardo suffered lead poisoning due to toxic pigments in paint.

But the plans are going down like a lead balloon with some scholars.

Nicholas Turner, a former curator of drawings at the Getty Museum, said: "It sounds a bit fanciful, slightly mad, as if the Leonardo bug has taken hold too firmly in the minds of these people.

"We know Mona Lisa was a specific person, she existed and it's her portrait. If Leonardo heard about all this, he would have a good chuckle."