ObjectiveTo explore the serologic and molecular biological identification methods of a rare Fy(a-b+ ) blood group and anti-Fyairregular antibody.
MethodsIn September 2018, one patient with chronic renal failure who was admitted to the Affiliated Hospital of Qingdao University and whose blood sample was sent to the Institute of Transfusion Medicine, Qingdao Blood Center for further blood type and irregular antibody identification due to cross-matching incompatibility was selected as the subject. This patient was male, Han nationality, and 72 years old, with blood transfusion histories. ABO and Duffy blood group identification, direct antiglobulin test, screening and identification of irregular antibodies for patient′s blood sample were carried out by test tube method. Two kinds of domestic (originated from yellow race) and imported (originated from white race) irregular antibodies screening cells and identification cells, as well as salt solution and anti-human globulin reagent were used for irregular antibodies screening and identification, respectively. The complete exon of Duffy gene of patient′s DNA sample was sequenced by Sanger dideoxy chain termination method. This study was in line withWorld Medical Association Declaration of Helsinkirevised in 2013.
ResultsThe test results of this patient′s blood and DNA samples were as follows: ① The patient was O blood type, RhD positive, and Fy (a-b+ ) blood type. The result of direct antiglobulin test was positive. ② The results of irregular antibody screening suggested the presence of alloantibodies and autoantibody in patient′s serum sample. The results of irregular antibody identification confirmed the irregular antibody was anti-Fyaalloantibody in the patient′s serum sample. ③DNA sequencing of Duffy gene exon displayed there was AA homozygous at c. 125, which confirmed the patient was a rare Fy(a-b+ ) blood group.
ConclusionFor accurately identify rare Fy(a-b+ ) blood group and irregular antibodies, it is necessary to using screening cells and identification cells from different ethnic origin for serologic test, combined with DNA sequencing technology.
