The Bournemouth tight-head prop has Italian blood because his father hails from Palermo on the island of Sicily.
With the Azzurri winless again from their opening three games of this year’s competition and England sitting second, Firetto says he will always support the underdog.
He said: “I would like to say I am pretty neutral but I will always back Italy - I have always had to back Italy because of my old man - and they are the underdogs.
“I will always support England but if Italy are playing England then I have got to support Italy just because of my dad.
“I have always supported them in football or rugby since I was a little kid even though I don’t think we have got a hope in hell of winning.”
Firetto has been at the fulcrum of a strong Bournemouth scrum this season.
He and the rest of the forwards have provided vital possession and strong platforms for their team-mates to then build upon.
Growing up, he said he idolised former Leicester Tigers’ prop Martin Castrogiovanni - who won over 100 caps for his country.
He was revered for being one of the most destructive forces in world rugby and was richly rewarded with moves to Toulon and Racing 92 at the end of his career.
But with Castrogiovanni retiring from the game in 2016, Firetto says he struggles to see the country of his father’s birth beating Eddie Jones’ England.
He added: “I don’t think Italy have ever beaten England before, even though they have beaten everyone else in the Six Nations.
“So usually I just put my head in my hands as we get beaten by about 50 points because England always seem to really turn it on against us.
“Italy have got quite a new team at the minute as well, but they have been pretty good so far.
“I think we have made it pretty awkward for teams to play against us and we were good against Ireland the other week.
“There have been some tight scores so far so the points difference is actually not as bad as what it has been so fingers crossed and we will see how it goes.”