[Improvement of gene analysis method in hemophilia A and its application of prenatal diagnosis]

Abstract

Objective: To establish a simple and rapid system for carrier detection and prenatal diagnosis in hemophilia A (CHA) family.

Methods: Long distance-polymerase chain reaction (LD-PCR) was selected for detection factor VIII intron 22 inversion. Polymorphism of factor VIII intragenic restriction fragment length polymorphism (RFLP) of Xba I and Hin d III, short tandem repeat (STR) within intron 13 and 22, as well as extragenic DXS52 (ST 14) variable number of tandem repeat (VNTR) were assayed by PCR and linkage analysis.

Results: Seventy-one females were diagnosed as carriers within 52 HA families. Twenty-one families were diagnosed to be factor VIII intron 22 inversion and 28 families were diagnosed by linkage analysis, whereas 3 families could not been diagnosed. Seventeen of 18 fetuses at risk were male. Ten of 17 male fetuses were shown to be affected and were subsequently aborted. Seven male fetuses were diagnosed to be not affected. One female fetus was identified to be HA carrier. One-year follow-up study demonstrated that these babies were normal and living well.

Conclusion: LD-PCR combined with multiple locus linkage analysis enables the direct and indirect detection of HA for carrier testing and prenatal diagnosis.