GENETIC-STUDIES OF HUMAN APOLIPOPROTEINS .4. STRUCTURAL HETEROGENEITY OF APOLIPOPROTEIN-H (BETA-2-GLYCOPROTEIN-I)

  • 1 March 1988
    • journal article
    • research article
    • Vol. 42  (3) , 452-457
Abstract
Human .beta.2-glycoprotein I has recently been identified as a component of several human plasma lipoprotein fractions and therefore termed as apolipoprotein H. Its metabolic function in lipid metabolism is not known with certainty, though it may be involved in very-low-density-lipoprotein metabolism. Previously, inherited quantitative variation in .beta.2-glycoprotein I has been suggested in man. In this investigation, we document the evidence of genetically determined structural polymorphism of apolipoprotein H or .beta.2-glycoprotein I by using thin-layer polyacrylamide isoelectric focusing gels followed by immunological identification by double antibody staining. The apolipoprotein H structural locus is characterized by the occurrence of three common alleles in U.S. whites and blacks. The frequency distributions of the three alleles designated APO H*1, APO H*2, and APO H*3 are .059, .882, and .059 in whites and .017, .902, and .068 in blacks, respectively. In addition, the gene product of a fourth allele, APO H*4, has been observed at polymorphic frequency in black individuals and may represent a black marker variant. Family data confirm the hypothesis of four alleles at a single APO H gene locus with an autosomal codominant pattern of inheritance.