There are at least three kind of alleles that have unknown-biochemical function

*Known PGx alleles that are classified with unknown functional status by PharmGKB

In the CPIC guidelines, some PGx alleles have unknown bio-chemical functional status. The dosing recommendation for such patients is to follow the normal medication advice. There are PGx-alleles that are classified with bio-chemical function, and otherwise, all patients without a known PGx-allele match also have unknown function.