title: FY*A silencing by the GATA-motif variant FY*A(-69C) in a Caucasian family.
abstract: BACKGROUND
  The c.1-67C variant polymorphism in a GATA motif of the FY promoter is known to result in erythroid-specific FY silencing, that is, in Fy(a-) and Fy(b-) phenotypes. A Caucasian donor presented with the very rare Fy(a-b-) phenotype and was further investigated.
  
  
  METHODS
  Genomic DNA was analyzed by sequencing to identify the cause of the Fy(a-b-) phenotype. Samples were collected from some of his relatives to establish a correlation between the serology and genotyping results. Red blood cells were analyzed by gel column agglutination and flow cytometry. Genomic DNA was analyzed on genotyping microarrays, by DNA sequencing and by allele-specific PCR.
  
  
  RESULTS
  In the donor, a single-nucleotide polymorphism T>C within the GATA motif was found at Position c.1-69 of the FY promoter and shown to occur in the FY*A allele. His genotype was found to be FY*A(-69C), FY*BW.01. In six FY*A/FY*B heterozygous members of the family, a perfect correlation was found between the presence vs. absence of the FY*A(-69C) variant allele and a Fy(a-) vs. Fy(a+) phenotype.
  
  
  CONCLUSIONS
  The location of the c.1-69C polymorphism in a GATA motif whose disruption is known to result in a Fy null phenotype, together with the perfect correlation between the presence of the FY*A(-69C) allele and the Fy(a-) phenotype support a cause-effect relationship between the two.
authors.affiliation: Institute of Hematology and Blood Transfusion, Prague, Czech Republic.
authors.forename: Martin
authors.initials: M
authors.lastname: Písačka
authors.affiliation: Institute of Hematology and Blood Transfusion, Prague, Czech Republic.
authors.forename: Iuri
authors.initials: I
authors.lastname: Marinov
authors.affiliation: Institute of Hematology and Blood Transfusion, Prague, Czech Republic.
authors.forename: Miroslava
authors.initials: M
authors.lastname: Králová
authors.affiliation: Institute of Hematology and Blood Transfusion, Prague, Czech Republic.
authors.forename: Jana
authors.initials: J
authors.lastname: Králová
authors.affiliation: Department of Hematology and Blood Transfusion, Central Military Hospital, Prague, Czech Republic.
authors.forename: Michaela
authors.initials: M
authors.lastname: Kořánová
authors.affiliation: Department of Hematology and Blood Transfusion, Central Military Hospital, Prague, Czech Republic.
authors.forename: Miloš
authors.initials: M
authors.lastname: Bohoněk
authors.affiliation: Progenika, Inc., Medford, Massachusetts.
authors.forename: Chhavi
authors.initials: C
authors.lastname: Sood
authors.affiliation: Progenika, Inc., Medford, Massachusetts.
authors.forename: Gorka
authors.initials: G
authors.lastname: Ochoa-Garay
mesh_terms: D000483:Alleles; D004375:Duffy Blood-Group System / Q000235:genetics*; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D010375:Pedigree; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics; D044465:White People
chemical_list: D004375:Duffy Blood-Group System