In order to identify and track Mutant entities in the UK the Avalon Institute employs GWENN, an old computer system built around an ancient relic, Guinevere’s looking glass. The system works by isolating a genetic marker, in this particular use case the Mutant X-Gene, and mapping out where entities carrying this genetic marker can be found (accurate to about a 500-meter radius).

There are ways to shield oneself from being detected by GWENN, and the system has created some false positives in the past due to, for example, family connections between the operator and the tracked individual. Depending on the variables entered into the machine, a requested operation can take several hours to complete.

An operator is required to stay with the computer to guide and filter through the results and narrow the search parameters as results start to come in as well as address any errors as they occur.

GWENN is situated in the private (and more or less secret) wing of Avalon Institute that also contains the Strat-Room, Quantum Knights Barracks, the Danger Room, and the hangar containing Nessie (the institute's Concorde 1001).