XE is a "recombinant" which is a mutation of BA'1 and BA.2 Omicron strains. Recombinant mutations emerge when a patient is infected by multiple variants of COVID. The variants mix up their genetic material during replication and form a new mutation, UK experts said in a paper published in British Medical Journal, NDTV reported.
The World Health Organization said that the new mutation XE appears to be 10 per cent more transmissible than the BA.2 sub-variant of Omicron.
"Early-day estimates indicate a community growth rate advantage of 10 percent as compared to BA.2, however, this finding requires further confirmation," the global health body added.
The UK Health Security Agency (UKHSCA) said it was studying XE - a mutation of the BA.1 and BA.2 Omicron strains, referred to as a "recombinant".
Britain's health agency said that XE was first detected on January 19 and 637 cases of the new variant have been reported yet.
Meanwhile, the BA.2 sub-variant of Omicron is spreading rapidly across the globe. Some 4.9 million people in the UK are estimated to have had COVID-19 in the week ending March 26, or 600,000 more than the previous week, the latest survey by the Office for National Statistics said.