Officially named B.1.617, it is not clear how the variant got into the UK or when.
B.1.617 has been described by some scientists as a “double mutant” variant due its characteristics.
In simple terms, a “variation” is a type of the coronavirus. Each one has “mutations” which are like features.
The B.1.617 variant has two mutations – E484Q and L452R – which for the first time have been seen in a singular variant, B.1.617.
Paul Hunter, professor in medicine at the University of East Anglia, said this is “causing people to be concerned”.
The worry is that when combined, these two mutations are far more infectious or able to evade immunity from either prior infection or vaccination, as has been shown to be the case with the South African and Brazilian variants.
But not a lot is known about the two mutations at the moment.
Prof Hunter described the two mutations as “escape mutations”.
It means they could help the variant escape antibodies in the blood which are there to fight off coronavirus infection.
“There’s laboratory evidence that both of these are escape mutations,” he said.
“Basically, applying what we know about other human coronaviruses would suggest that this is going to be even less controlled by vaccine.”
“But we don’t know that for certain at the moment.”
He said two of these mutations together could be “a lot more problematic” than just singular escape mutations in the South African and Brazilian variants.
Both these strains contain a mutation called E484K, which has been shown to dodge antibodies.