Objective: Screening the intron 1 inversion of factor VIII (FVIII) in the population of severe haemophilia A(HA) in China and performing carrier detection and prenatal diagnosis.
Methods: Using LD-PCR to detect intron 22 inversions and multiple-PCR within two tubes to intron 1 inversions in severe HA patients. Carrier detection and prenatal diagnosis were performed in affected families. Linkage analysis and DNA sequencing were used to verify these tests.
Results: One hundred and eighteen patients were seven diagnosed as intron 22 inversions and 7 were intron 1 inversions out of 247 severe HA patients. The prevalence of the intron 1 inversion in Chinese severe haemophilia A patients was 2.8% (7/247). Six women from family A and 2 from family B were diagnosed as carriers. One fetus from family A was affected fetus.
Conclusion: Intron 1 inversion could be detected directly by multiple-PCR within two tubes. This method made the strategy more perfective in carrier and prenatal diagnosis of haemophilia A.