title: Molecular studies reveal that A134T, G156A and G1333A SNPs in the CD177 gene are associated with atypical expression of human neutrophil antigen-2.
abstract: OBJECTIVE
  The human neutrophil antigen-2 (HNA-2) is expressed on a subpopulation of neutrophils as most subjects present a negative plus a positive HNA-2 population of neutrophils. The number of neutrophils expressing HNA-2 is variable and may increase in pregnancy, infections, myeloproliferative disorders and after G-CSF. This study investigated the presence of polymorphisms in the gene encoding HNA-2 (CD177) in individuals presenting different patterns of antigen expression and determined the association of single nucleotide polymorphisms (SNPs) with the heterogeneous HNA-2 expression.
  
  
  METHODS
  Flow cytometry was employed to analyse the HNA-2 expression on neutrophils from 135 healthy subjects using two monoclonal antibodies (TAG4, 7D8). Sequencing reactions were performed on subjects whose antigen expression was low (< or = 50%), high (> or = 80%) or atypical (a nonreactive population plus two distinct positive cell populations).
  
  
  RESULTS
  Five SNPs were detected, two of them (A793C, G1084A) were related to a low expression of HNA-2 (P = 0.031 and P = 0.004). Atypical antigen expression was observed in 5.9% (8/135) of the individuals, three nonpregnant women and five men. In these cases, the cDNA sequences revealed three SNPs (A134T, G156A and G1333A) strongly related to this atypical HNA-2 expression (P = 0.004, P = 0.006 and P < 0.0001, respectively).
  
  
  CONCLUSIONS
  Our data show that polymorphisms in the CD177 are associated with variations in the HNA-2 expression and may be the cause of atypical expressions.
authors.affiliation: Discipline of Hematology and Hemotherapy, Federal University of São Paulo, São Paulo, Brazil.
authors.forename: E
authors.initials: E
authors.lastname: Moritz
authors.forename: A K
authors.initials: AK
authors.lastname: Chiba
authors.forename: E Y
authors.initials: EY
authors.lastname: Kimura
authors.forename: D
authors.initials: D
authors.lastname: Albuquerque
authors.forename: F P
authors.initials: FP
authors.lastname: Guirão
authors.forename: M
authors.initials: M
authors.lastname: Yamamoto
authors.forename: F F
authors.initials: FF
authors.lastname: Costa
authors.forename: J O
authors.initials: JO
authors.lastname: Bordin
mesh_terms: D000328:Adult; D005260:Female; D005434:Flow Cytometry; D058851:GPI-Linked Proteins; D006801:Humans; D007519:Isoantigens / Q000096:biosynthesis / Q000097:blood / Q000235:genetics* / Q000276:immunology; D008297:Male; D008562:Membrane Glycoproteins / Q000096:biosynthesis / Q000097:blood / Q000235:genetics* / Q000276:immunology; D008875:Middle Aged; D009504:Neutrophils / Q000276:immunology* / Q000378:metabolism; D020641:Polymorphism, Single Nucleotide; D011956:Receptors, Cell Surface / Q000096:biosynthesis / Q000097:blood / Q000235:genetics* / Q000276:immunology; D055815:Young Adult
chemical_list: C407242:CD177 protein, human; D058851:GPI-Linked Proteins; D007519:Isoantigens; D008562:Membrane Glycoproteins; D011956:Receptors, Cell Surface