한국인에서의 혈우병 B (Factor IX gene)의 다형성을 알아보기 위한 실험으로, 정상인 한국여성 50명으로부터 genomic DNA를 추출하였다. 이 genomic DNA를 주형으로 하여 각 polymorphic sites(Dde I 과 Mnl I site)를 포함하는 부위를 증폭하도록 설계된 primers를 이용하여 PCR을 수행하였다. 인공합성 DNA 단편을 알맞은 제한 효소로 처리하고, polymorphic sites의 유,무를 관찰하여 그 다형성을 고찰하였다. 실험 결과, 한국인에서 Dde I과 Mml I-RFLP에서 산출된 PIC는 0.0%로 Caucasian이 경우와 매우 큰 차이를 나타내었다. 따라서 백인 또는 다른 민족 집단에서 확립된 진단 방법은 한국인에게 적용될 수 없음을 보였다.

Hemophilia B, a human chromosome X-linked recessive disease, is a bleeding disorder resulting from defect or abnormality in blood coagulation facotr IX, DNA-based prenatal diagnosis or carrier detection for hemophilia B in Korean has been developed by analyzing restriction fragment length polymorphisms(RFLPs). Two phlymorphisms(Dde I and Mnl I) were investigated as follow. Genomic DNAs were extracted from blood of 50 females at the age of twenty. The primers were chemically synthesized by the method of phosphoamidite. Mnl I primers were derived from exon 6, while Dde I primers, from the flanking sequences of intron 1 of the factor IX gene. Genomic DNAs were amplified with Mnl I primers to generate 405 nt long fragments in all cases. They were digested with Mnl I to analyze the polymorphic site on agarose gel. No Mnl I polymorphic site was found in all cases. Also, the genomic DNAs were amplified with Dde I primers to generate 320 nt long fragments in all cases. These results are not corrclated with those obtained from the Caucasian. It suggests that Korean could exhibit different patterns of Dde I and Mnl I polymorphisms in the gene for blood coagulation factor IX. Direct sequencing of the polymorpic sites will confirm the above suggestion.