Premium
The rarer polymorphic variants of platelet glycoprotein Ib are more prevalent in African Americans than in Caucasians or Asians
Author(s) -
Kermode John C,
Choi Jaehwa,
Kanyicska Bela,
Chitta Mohan S,
Park Sangwon,
Jana Tanima,
Clark Shawna,
Randolph Erica,
Trehan Roshni,
Zheng Qi
Publication year - 2007
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.21.6.a1166-a
Subject(s) - genetics , biology , allele , linkage disequilibrium , von willebrand factor , tandem repeat , platelet membrane glycoprotein , allele frequency , platelet glycoprotein gpib ix complex , gene , glycoprotein ib , polymorphism (computer science) , variable number tandem repeat , haplotype , glycoprotein , platelet , immunology , genome
Interaction of von Willebrand factor (VWF) with circulating blood platelets is the initial trigger for thrombosis in an arterial stenosis. Polymorphisms in the gene encoding the VWF receptor, platelet glycoprotein Ib (GpIb), may thus alter the risk of cardiovascular disease. One such polymorphism is a C/T dimorphism at nucleotide 482 in the GpIbα gene; it alters the codon for amino acid 161 from threonine to methionine within the VWF binding domain. We have devised a method based on the real‐time polymerase chain reaction to assay this dimorphism. Another polymorphism involves a variable number of tandem repeats (VNTR) of a 39‐nucleotide sequence encoding part of the extracellular portion of GpIbα; this sequence may occur once (VNTR‐D allele), twice (VNTR‐C) or three times (VNTR‐B). We have genotyped individuals from three racial groups for both polymorphisms. Our data indicate that the rarer 482 T and VNTR‐B alleles are much more prevalent in African Americans than in Caucasians or Asians. Moreover, the pattern of linkage disequilibrium among these polymorphisms is weaker in African Americans and Asians than in Caucasians. These observations suggest that studies in African Americans will be more powerful at elucidating the mechanism whereby either polymorphism alters the propensity for cardiovascular disease. [Supported by the National Science Foundation and the Mississippi Functional Genomics Network.]