Orosomucoid phenotyping with monoclonal antibodies:polymorphic occurrence of ORM1*Q0 in aboriginal Taiwanese populations.

Three monoclonal antibodies (OR35, OR40 and OR48) against orosomucoid (ORM) were prepared for the phenotyping of the human ORM system. The OR35 and OR48 antibodies recognized ORM1 and ORM2 products, respectively. OR40 reacted strongly to the products of ORM1 but poorly to those of ORM2. With the help of these monoclonal antibodies, ORM phenotyping was performed on 658 individuals from nine subpopulations of aboriginal Taiwanese, with close attention to two individuals with an ORM1 Q0 homozygous phenotype. The ORM1*Q0 allele was found to be at a polymorphic frequency in eight of the nine subpopulations.