title: Expansion of the P blood group system of the horse.
mesh_terms: D000483:Alleles; D000818:Animals; D001789:Blood Group Antigens / Q000235:genetics*; D005787:Gene Frequency; D006736:Horses / Q000097:blood* / Q000235:genetics; D011110:Polymorphism, Genetic; D013045:Species Specificity
chemical_list: D001789:Blood Group Antigens