title: Study of MICA alleles in 201 African Americans by multiplexed single nucleotide extension (MSNE) typing.
abstract: We have developed a method for major histocompatibility complex class I chain-related gene A (MICA) genotyping using multiplexed single nucleotide extension (MSNE) and flow cytometric analysis of an array of fluorescent microspheres. This technique employs a polymerase chain reaction-derived target DNA containing all the polymorphic sites of MICA, synthetic complementary primers, biotinylated dideoxynucleotide triphosphate, fluorescent reporter molecules (streptavidin-phycoerythrin), and thermophilic DNA polymerase. Genomic DNA was amplified by MICA locus-specific primers and the MSNE reactions were carried out in the presence of 30 MSNE primers used to assay polymorphisms in exons 2, 3, and 4 of the MICA genes. Thirty-two previously typed cell lines were used as reference material. The MICA gene frequencies among 201 African-American unrelated donors were determined. Of 51 previously known alleles, 18 were observed in African-Americans, compared to 16 that were found in North American Caucasians and 9 in South American Indians, suggesting a more diversified allelic distribution in African-Americans. MICA*00201 and MICA*00801 were the two most frequent alleles in African-Americans. We observed a high degree of linkage disequilibrium between certain alleles of MICA and of human leukocyte antigen-B in the African-American population. The methodology described here offers a powerful new approach to DNA typing of the MICA alleles.
authors.affiliation: University of Texas Southwestern Medical Center, Dallas, TX 75390-8886, USA.
authors.forename: Yanzheng
authors.initials: Y
authors.lastname: Zhang
authors.forename: Mei
authors.initials: M
authors.lastname: Han
authors.forename: Robert
authors.initials: R
authors.lastname: Vorhaben
authors.forename: Chris
authors.initials: C
authors.lastname: Giang
authors.forename: Bhavna
authors.initials: B
authors.lastname: Lavingia
authors.forename: Peter
authors.initials: P
authors.lastname: Stastny
mesh_terms: D001741:Black or African American / Q000235:genetics*; D000483:Alleles; D002460:Cell Line; D015395:Histocompatibility Antigens Class I / Q000145:classification / Q000235:genetics*; D006801:Humans; D015810:Linkage Disequilibrium; D021141:Nucleic Acid Amplification Techniques; D011110:Polymorphism, Genetic
chemical_list: D015395:Histocompatibility Antigens Class I; C099187:MHC class I-related chain A