Objective: To improve the gene diagnosis,carrier detecting and prenatal diagnosis for hemophilia A families to a maximum.
Methods: Long distance PCR (LD-PCR) was used to detect FVIII gene inversion among 26 patients with severe HA and their female offspring to identify those with FVIII gene inversion and its carriers. Three gene linkage analysis based upon PCR, Bcl I PCR/RFLP, St14 VNTR/PCR analysis and two simple dinucleotides repeats polymorphism analysis were used among 19 non-inversion HA families for indirect diagnosis.
Results: Sixteen families with severe HA were detected by LD-PCR among the 26 hemophilia A families. Seven were confirmed as with FVIII gene inversion (43.8%). The diagnostic rates by the above mentioned three indirect diagnostic techniques among nineteen families without gene inversion were 84.2%, 68.4% and 89.5% respectively. Confirmed diagnosis was successfully made among all of the HA families by the four techniques.
Conclusion: Gene diagnosis and carrier detecting can be confirmed among almost all of the HA families can be diagnosed by the combined use of the four direct and indirect gene diagnostic methods.