The Fya and Fyb antigens were reported in 1950 and 1951 respectively. Anti-Fya and anti-Fyb have both been implicated in immediate and delayed Haemolytic Transfusion Reactions and Haemolytic Disease of the Newborn.

The reagent will cause indirect agglutination (clumping) of test red cells, that carry the Fy(a) antigen, in the antiglobulin phase of testing. No agglutination generally indicates the absence of the the Fy(a) antigen.

Lorne Monoclonal Fya blood grouping reagent contains human monoclonal antibodies diluted in a phosphate buffer containing sodium chloride and bovine albumin.