*High Gravity Ale* has been identified using polymerase chain reaction (PCR) to contain the glucoamylase gene (STA1), which can be an indicator of S. cerevisiae var. diastaticus. As such, this strain has the ability to utilize some dextrins which are unfermentable to most species of S. cerevisiae, and thus achieve a very high level of attenuation. However, this strain is not considered a contaminant and will not over-attenuate finished beer when a high level of attenuation is expected.