Polymorphic plasma postalbumins of some domestic animals (pig PO2, horse Xk and dog Pa proteins) identified as homologous to human plasma alpha 1B-glycoprotein.

Pig, horse and dog plasma proteins, separated by horizontal polyacrylamide gel electrophoresis (pH 9.0) and electrophoretically transferred to nitrocellulose membranes, were tested for cross-reaction with antiserum to human plasma alpha 1B-glycoprotein (alpha 1B). The results showed that one previously reported polymorphic plasma postalbumin in each of these species (pig PO2, horse Xk and dog Pa protein) was homologous to human plasma alpha 1B. In the light of the previously known genetic linkages in these species, this implied: (1) alpha 1B gene is close linked to Phi, Pgd and Hal (halothane sensitivity locus) loci in pigs; and (2) alpha 1B gene is linked to ME1 and Phi loci in horses. This suggested that the alpha 1B gene may also be found to be closely linked to gene(s) controlling susceptibility to malignant hyperthermia in humans and other mammals.