Approximately 91% of people test positive for Sd(a) through<unk>  typing, and 96% test positive through urine testing. The Sd(a++) phenotype is rare, especially in Europe, but may be more common in East Asian populations.
Sid blood group system
Lan blood group system
Junior blood group system
Rh blood group system
Augustine blood group system
Vel blood group
Hh blood group
P1PK blood group system