title: [Genotyping of blood group systems at the CNRGS. I: FY, JK, MNS systems].
abstract: OBJECTIVE
  Determination of blood group antigens from data obtained by using molecular methods (genotyping) has become an indispensable tool in the specialized immunohematology laboratories. The French National Reference Centre for Blood group typing (CNRGS) routinely performs genotyping of the FY, JK and MNS system (common genotyping), providing a phenotype deduced from genotyping data for FY1, FY2, JK1, JK2, MNS3 and MNS4 antigens.
  
  
  METHODS
  We performed a study to evaluate the common genotyping prescriptions referred to the CNRGS over the last three years.
  
  
  RESULTS
  Between February 2006 and February 2009, the CNRGS performed 2392 genotyping, including 981 common genotyping. Analysis of 172 common genotyping performed in 2008 showed that 63.8% of the prescriptions expressed a genotyping demand. Of the latter, 42.7% were genotyping prescriptions only, whereas 57.2% were prescriptions of genotyping associated with alloantibody identification. All prescriptions refer to blood group genotyping indications issued from guidelines, with no incorrect prescription, that are patients transfused within four months before blood sampling in 63.6% of cases or a positive direct antiglobulin test in 24.5% of cases. Lastly, 36% of the blood samples referred to the CNRGS had no genotyping prescription. Yet, common genotyping was performed by the CNRGS to get complete immunohematology data for antibody identification.
  
  
  CONCLUSIONS
  Usefulness of blood group genotyping in specialized immunohematology laboratories is obvious. However, the strategy for implementation of molecular methods remains to be defined. Use of high-throughput DNA analysis should change our way of working.
authors.affiliation: Centre National de Référence pour les Groupes Sanguins, Institut National de la Transfusion Sanguine, 75522 Paris cedex 11, France. bnpham@ints.fr
authors.forename: B N
authors.initials: BN
authors.lastname: Pham
authors.forename: T
authors.initials: T
authors.lastname: Peyrard
authors.forename: M
authors.initials: M
authors.lastname: Ripaux
authors.forename: S
authors.initials: S
authors.lastname: Bourgouin
authors.forename: S
authors.initials: S
authors.lastname: Martin-Blanc
authors.forename: P-Y
authors.initials: PY
authors.lastname: Le Pennec
authors.forename: P
authors.initials: P
authors.lastname: Rouger
mesh_terms: D001788:Blood Grouping and Crossmatching; D004375:Duffy Blood-Group System / Q000235:genetics*; D005838:Genotype; D006801:Humans; D007667:Kidd Blood-Group System / Q000235:genetics*; D008951:MNSs Blood-Group System / Q000235:genetics*
chemical_list: D004375:Duffy Blood-Group System; D007667:Kidd Blood-Group System; D008951:MNSs Blood-Group System