目的首次调查北京地区人群体凝血因子B(FB)DNA水平的遗传多态性。方法应用PCR-STR技术。结果推算出FBDNA水平的基因分布频率,符合Hard-Weinberg平衡定律。结论对法医的办案工作,具有一定的实用性和推广意义。 Objective To investigate the genetic polymorphism of DNA level of human coagulation factor B (F  B) in Beijing population for the first time. Methods PCR-STR technique was used. Results The frequency of gene distribution at FBDNA level was calculated and in accordance with Hard-Weinberg equilibrium law. Conclusion The case handling of forensic medicine has certain practicality and promotion significance.