What is "verdesse"

Verdesse is a white French wine grape variety grown primarily in the Bugey AOC of eastern France (though it is not currently permitted in the AOC wine). It is also permitted under the Vin de Savoie AOC for wines produced in the Isère department up to a maximum allowance of 10%. Ampelographers believe that the variety is likely very old and originated along the Drac and Grésivaudan valleys in Isère.