目的 加强对遗传性凝血因子Ⅻ（FⅫ）缺乏症的了解。方法 回顾分析1例复合杂合变异致FⅫ缺乏症的临 床资料，并检索和复习近10年的相关文献。结果 女性患儿，6岁时因拟行腹股沟疝手术发现凝血功能异常，无出血表现， 无特殊用药史及家族史；凝血功能示活化部分凝血活酶时间（APTT）明显延长，凝血酶原时间（PT）正常，APTT纠正试验 （即刻和延迟）均能纠正，血浆凝血因子活性检测（Ⅻ：C）为1.3%。基因检测发现患儿F12基因存在2个杂合变异，第14 号外显子上c.G 1681 A（编码区1681号核苷酸由G变为A），来自于母亲；第11号外显子上c.G1330T（编码区1330号核苷 酸由G变为T），来自于父亲；患儿父母均为携带者，无自发性出血表现；ACMG评分为致病性变异。结论 基因检查有助 于遗传性FⅫ缺乏症的诊断，扩充了遗传性FⅫ缺乏症的基因变异谱。

Objective To strengthen the understanding of hereditary factor Ⅻ (FⅫ) deficiency. Methods The clinical data of hereditary coagulation factor Ⅻ (FⅫ) deficiency caused by compound heterozygous variation in a child were retrospectively analyzed and the related literatures in recent 10 years were reviewed. Results A girl was found to have abnormal coagulation function due to inguinal hernia surgery at the age of 6 . She has no bleeding, chronic disease history or family history. The coagulation function showed that activated partial thromboplastin time (APTT) was significantly prolonged, prothrombin time (PT) was normal, and APTT correction test (immediate and delayed) could be corrected. The plasma coagulation factor activity (Ⅻ:C) was 1 . 3 % (reference range: 50 %- 150 %). Two heterozygous variations were detected in F12 gene in the child by gene sequencing. The variation of c.G 1681 A (nucleotide 1681 in coding region changing from G to A) in exon 14 came from the mother, and the variation of c.G 1330 T (nucleotide 1330 in coding region changing from G to T) in exon 11 came from the father. The parents of the child were carriers, and they had no spontaneous bleeding. It was determined as pathogenic variation by ACMG. Conclusion Genetic testing is helpful for the diagnosis of hereditary FⅫ deficiency and the genetic variation information of hereditary FⅫ deficiency can be found.