We may have been enthralled with Leonardo da Vinci’s “Mona Lisa” and the figure’s famous ‘enigmatic smile’. Recurring debates would crop up, however, on the identity of the portrait. An Italian researcher has declared that the famous artist, Leonardo da Vinci had used a male model for his equally famous piece of work, “Mona Lisa”.

Silvano Vinceti, an Italian researcher has claimed in a recent press conference at the Foreign Press Association that a male apprentice and longtime companion was behind the famous painting. Vincenti, described by The Associated Press as a 'media-savvy writer and researcher', has named the male model as Gian Giacomo Caprotti, popularly known as Salai.

Vinceti explained that Salai began working for Leonardo in 1490 and stayed with the famous artist for two decades. The Italian researcher, added AP, that art historians have all earlier agreed that Salai was Leonardo’s lover.

To prove his point, Vinceti noted the ‘striking’ similarities in Mona Lisa’s nose and mouth with that of Leonardo’s apprentice.

"Salai was a favorite model for Leonardo," Vinceti said, according to AP. "Leonardo certainly inserted characteristics of Salai in the last version of the Mona Lisa."

Vinceti clarified, however, that Leonardo da Vinci could have been inspired by other influences earlier reported,including Lisa Gherardini, the wife of Florentine merchant Francesco del Giocondo. It could also be the noblewoman Beatrice D'Este, who was reportedly seen often by Da Vinci when he was painting. “The Last Supper”.

But the letters "S" and "L" that Vinceti has discovered recently has led the Italian researcher’s conclusion that the painter’s model could have been more likely to be Salai and Lisa.

Known for using what AP described as 'CSI-techniques' in his art researches, Vinceti has claimed that the "S" he found in the model’s eyes could stand for Salai and the Sforza dynasty, while the letter “L” could have represented Leonardo da Vinci’s name and that of Lisa Gherardini.

Vinceti’s recent pronouncement has again resulted in debtaes and conflicting art theories on the famous portrait, now on display at the Louvre Museum in Paris.