The present invention relates to phytases having at least 76% identity to a phytase derived from Hafnia alvei and comprises at least one modification in the amino acid sequence thereof. These phytase variants have modified, preferably improved, properties, such as, reduced protease sensitiliby, preferably they exhibit improved properties in respect of thermal performance, such as heat-stability (temperature stability, thermostability), steam stability, pelleting stability and/or temperature profile； and/or protease stability, in particular pepsin stability, pH profile, specific activity, substrate specificity, performance in animal feed(such as an improved release and/or degradation of phytate), susceptibility to glycation, and/or glycosylation pattern. The invention also relates to DNA encoding these phytases, methods of their production, as well as the use thereof, e.g. in animal feed and animal feed additives.
