Study on gene diagnosis of haemophilia A

Abstract

We have successfully diagnosised 24 individuals of 5 haemophilia A pedigrees with RFLP linkage analysis and gene amplification in vitro (PCR) technique. Detecting with the I₁₄-E₁₈, we found the carriers of family A and B were not heterozygotes of Bcl I RFLP. They were homozygotes of 3.0 kb/3.0 kb and 2.3 kb/2.3 kb respectively, while the carriers of family C and D were heterozygotes of 3.0 kb/2.3 kb and 3.3 kb/2.3 kb respectively. So it could be made gene diagnosis with Bcl I RFLP in family C and D. In family D, pathologic gene was linked to 3.3 kb band. We have exactly made gene diagnosis 10 family A and B with RFLP linkage analysis after PCR. Our results showed that the carriers of family A and B all were heterozygotes of 142 bp/99 bp, In family A and B, pathologic FVI gene was linked to 142 bp fragment.

With Bg1 I/DX₁₃, we made a RFLP linkage analysis of haemophilia A fetus at the early pregnant period, whose mother was heterozygote of 5.8 kb/2.8 kb, and the fetus was hemizygote of 2.8 kb/-. So it was very clear that the fetus was patient of haempphilia A. We suggested that the pregnant woman to induce abortion to prevent a sick baby from being born.

References

[1] 1989; 10(l2):643

[2] GitschierJ, et al.. Genetic mapping and diagnosis of hemophilia A achieved through a Bcl I polymorphism in the factor VI gene. Nature, 1985, 314: 738-740

[3] WionK L, et al.. A new polymorphism in the factor VI gene for prenatal diagnosis of hemophilia A. Nucleic Acid Res, 1986, 14(11): 4535-4542

[4] OberleI, et al.. Genetic screening for hemphilia A (Class hemophilia) with a polymorphic DNA probe. N Engl J Med, 1985, 3l2(11): 682-686

[5] Harper Ket al. A clinically useful DNA probe closely linked to hemophilia A. Lancet, l984;(2):6–8

[6] 1988:138

[7] DillonJ R, et al.. Recombinant DNA methodology, 1985WuhanJohn Wiley & Sons1-75

[8] GitschierJ, et al.. Characterization of the human factor VI gene. Nature, 1984, 312: 326-330

[9] KoganS C, et al.. An improved method for prenatal diagnosis of genetic disease by analysis of amplified DNA sequences. N Engl J Med, 1987, 317: 985-990

[10] SaikiR K, et al.. Primer-directed enzymatic amplification of DNA with a themostable DNA polymerase. Science, 1988, 239: 487-487