从北美和欧州曾报告应用五种RFLP(Restri-ction Fragment Length Polymor p-hisms)系统方法检测高加索人群中Ⅸ因子基因。显示基因片断的内切酶有TaqⅠ,Xmn Ⅰ,Dde Ⅰ,MsP Ⅰ和BamH Ⅰ。本文曾研究20例美籍华人,20例日本人和9例菲律宾人的RFLP标记。DNA样品曾用Taq Ⅰ,Xmn Ⅰ和MsP Ⅰ内切酶,并而Ⅸ因子CDNA探针作分子杂交。Taq Ⅰ查61个个染色体。Xmn Ⅰ查76个染色,MsP Ⅰ查57个染色,并与少数样品采用BamH Ⅰ和Dde Ⅰ It has been reported from North America and Europe that five kinds of RFLP (Restri-ction Fragment Length Polymor p-hisms) system were used to detect the gene of factor Ⅸ in Caucasian population. The endonucleases showing the gene fragments include Taq I, Xmn I, Dde I, MsP I and BamH I. This article has studied RFLP markers of 20 Chinese Americans, 20 Japanese and 9 Filipinos. DNA samples were subjected to molecular hybridization with Taq I, Xmn I and MsP I endonucleases and factor IX CDNA probe. Taq Ⅰ check 61 chromosomes. 76 were stained with Xmn Ⅰ, 57 stained with MsP Ⅰ, and a few samples were stained with BamH Ⅰ and Dde Ⅰ