IDENTIFICATION OF NEW APOLIPOPROTEIN-B EPITOPES AND HAPLOTYPES AND THEIR DISTRIBUTION IN SWINE POPULATIONS

Results from comparative immunogenetic studies on inheritance and iden tification of four new apolipoprotein B (apoB) allotypes and three add itional apoB haplotypes and their distribution in miniature and domest ic swine are presented. Immunological surveys on the four new and 16 p reviously described Lpb allotypes and genetic analysis of their segreg ation in progenies, of miniature and domestic swine and their crosses, indicate that three new allotypes designated Lpb9, Lpb10 and Lpb101 a re individual (mutant) apoB epitopes, each representing a discriminati ng marker for one of the new apoB haplotypes specified by three new ap oB alleles designated Lpb(9), Lpb(10) and Lpb(101). The fourth allotyp e, Lpb20, is one of the common epitopes forming the alternative epitop e pair with Lpb10, and is a constituent of each of the eight previousl y described and two new apoB haplotypes. The new apoB alleles have so far been found only in miniature swine, with Lpb(10) being the most fr equent in the Gottingen, Vietnamese Pot-belly and Japanese Miniature, Lpb(9) was detected only in Minnesota Miniature and Lpb101 only in Vie tnamese Potbelly. The common allotype, Lpb20, shares immunological sim ilarities with human apoB indicating its ancestral origin, whereas non e of the alloreagents detecting the three individual apoB variants, Lp b9, Lpb10 or Lpb101, showed cross-reactivity with human apoB, suggesti ng their exclusive swine origin and evolvement during speciation throu gh mutations.