What is the difference between the genetic and serological tests for blood type?

Genetic test K793 identifies recessive b alleles which are associated with blood type B. By analysing these mutations together, it is possible to predict the type B blood type in cats.
Genetic test K300, available for Ragdolls, identifies the AB allele and is associated with type AB blood in Ragdoll cats.

Another method to identify cat blood types, is serology. This method does not give information about the genetic background in a direct way and is therefore not suitable to use as a solely method when making breeding choices. Serologic blood typing is mainly used for blood transfusions and can only be performed on whole blood (EDTA or Heparin).

More information regarding cat blood types and which tests to use can be found in the knowledgebase.