passages: 3018
passages: document
passages: Paternal RHD zygosity determination in Tunisians : evaluation of three molecular tests . BACKGROUND The choice of a molecular test for first intention determination of paternal RHD zygosity , before entering into invasive diagnostics , is important for the management of pregnancies at risk of haemolytic disease of the foetus and newborn related to anti-RhD . MATERIALS AND METHODS RHD zygosity was evaluated in 370 RH:1 Tunisian donors by polymerase chain reaction - sequence-specific polymorphism ( PCR-SSP ) analysis and polymerase chain reaction - restriction fragment length polymorphism ( PCR-RFLP ) amplification of hybrid Rhesus box and by real time quantitative polymerase chain reaction ( RQ-PCR ) specific for RHD exon 5 . To evaluate the accuracy of molecular tests in the cases of discordant results , the ten exons of RHD and Rhesus boxes were amplified by PCR and sequenced . RESULTS Molecular investigations revealed that our 370 donors comprise 193 dizygous and 145 hemizygous individuals and 32 subjects whose zygosity remains unknown . Positive predictive values were higher than 99 % for all the methods , reaching 100 % for RQ-PCR . Negative predictive values were 83.24 % , 87.27 % and 98 % for PCR-SSP , PCR-RFLP and RQ-PCR respectively . This study also revealed 19 novel Rhesus box polymorphisms and three novel RHD alleles : RHD ( Trp185Stop ) , RHD ( Ala176Thr ) and RHD ( Ile342Ile ) . DISCUSSION RQ-PCR is the most convenient method for first intention determination of paternal RHD zygosity in Tunisians . However , taking into account positive and negative predictive values , PCR-RFLP could be an alternative despite the heterogeneity of Rhesus boxes and the complexity of RHD .
entities: 3019
entities: Intervention_Other
entities: molecular test
entities: 3020
entities: Intervention_Other
entities: polymerase chain reaction - restriction fragment length polymorphism ( PCR-RFLP )
entities: 3021
entities: Intervention_Other
entities: real time quantitative polymerase chain reaction ( RQ-PCR )
entities: 3022
entities: Intervention_Other
entities: RQ-PCR
entities: 3023
entities: Intervention_Other
entities: PCR-RFLP
entities: 3024
entities: Outcome_Other
entities: Positive predictive values
entities: 3025
entities: Outcome_Other
entities: Negative predictive values
entities: 3026
entities: Outcome_Physical
entities: Rhesus box polymorphisms
entities: 3027
entities: Outcome_Physical
entities: RHD alleles :
entities: 3028
entities: Participant_Condition
entities: Tunisians :
entities: 3029
entities: Participant_Sample-size
entities: 370
entities: 3030
entities: Participant_Condition
entities: RH:1
entities: 3031
entities: Participant_Sample-size
entities: Tunisian donors
entities: 3032
entities: Participant_Sample-size
entities: 370 donors