CAJ | 학술논문

目的对1个姑表近亲结婚的遗传性凝血因子Ⅻ(coagulation factorⅫ,FⅫ)缺陷症家系进行基因分析,探讨其分子发病机制.方法检测FⅫ缺陷患者家系活化部分凝血活酶时间( activated partial thromboplastin time,APTT),血浆FⅫ活性(FⅫprocoagulant activity,FⅫ∶ C)和血浆FⅫ抗原(FⅫantigen,FⅫ∶Ag)含量等凝血指标;PCR扩增先证者及其家系成员FⅫ基因的第1～14外显子及其侧翼序列,PCR产物纯化后测序,发现突变位点则反向测序以证实.结果先证者APTT明显延长,为157.5 s(正常为27.0～41.0 s),其子APTT为48.3s,轻度延长,家系其他成员APTT在正常范围.先证者FⅫ∶C和FⅫ∶Ag水平均＜1％；其妻子、女儿、儿子和母亲的FⅫ∶C分别为51％、21％、21％和50％,FⅫ∶Ag水平分别为42％、32％、37％和48％.先证者FⅫ基因第14外显子测序结果出现g.8699G＞A纯合型错义突变,导致第542位氨基酸甘氨酸变成丝氨酸(Gly542Ser),其母亲、女儿和儿子均为Gly542Ser杂合型.先证者及家系成员FⅫ基因第1外显子启动子区第46位C→T多态性均为46T/T型.结论该遗传性凝血因子Ⅻ缺陷症家系先证者FⅫ基因第14外显子存在g.8699G＞A纯合型错义突变,导致Gly542Ser,推测与父母近亲结婚有关.Gly542Ser和46T/T与该遗传性凝血因子Ⅻ缺陷症家系FⅫ水平降低有关.
목적 대1개고표근친결혼적유전성응혈인자Ⅻ(coagulation factorⅫ,FⅫ)결함증가계진행기인분석,탐토기분자발병궤제.방법 검측FⅫ결함환자가계활화부분응혈활매시간( activated partial thromboplastin time,APTT),혈장FⅫ활성(FⅫprocoagulant activity,FⅫ∶ C)화혈장FⅫ항원(FⅫantigen,FⅫ∶Ag)함량등응혈지표;PCR확증선증자급기가계성원FⅫ기인적제1～14외현자급기측익서렬,PCR산물순화후측서,발현돌변위점칙반향측서이증실.결과 선증자APTT명현연장,위157.5 s(정상위27.0～41.0 s),기자APTT위48.3s,경도연장,가계기타성원APTT재정상범위.선증자FⅫ∶C화FⅫ∶Ag수평균＜1％；기처자、녀인、인자화모친적FⅫ∶C분별위51％、21％、21％화50％,FⅫ∶Ag수평분별위42％、32％、37％화48％.선증자FⅫ기인제14외현자측서결과출현g.8699G＞A순합형착의돌변,도치제542위안기산감안산변성사안산(Gly542Ser),기모친、녀인화인자균위Gly542Ser잡합형.선증자급가계성원FⅫ기인제1외현자계동자구제46위C→T다태성균위46T/T형.결론 해유전성응혈인자Ⅻ결함증가계선증자FⅫ기인제14외현자존재g.8699G＞A순합형착의돌변,도치Gly542Ser,추측여부모근친결혼유관.Gly542Ser화46T/T여해유전성응혈인자Ⅻ결함증가계FⅫ수평강저유관.
Objective To analyze genetic mutation and explore its molecular pathogenesis for an hereditary coagulation factor Ⅻ deficiency in a pedigree featuring consanguineous marriage. Methods Activated partial thromboplastin time(APTT)、FⅫ procoagulant activity(FⅫ:C)、FⅫ antigen(FⅫ ∶ Ag)and other coagulant parameters were assayed. For the proband and his family members,exons 1 ～ 14,introns including the splice junctions of the FⅫ gene were amplified with polymerase chain reaction(PCR).The PCR product was purified and sequenced. The mutations were confirmed by sequencing the complimentary strand.Results The proband has featured prolonged APTT at 157.5 s(reference range,27.0～41.0 s).The APTT of his son has increased slightly at 48.3 s.The remaining members of the family were in normal range.FⅫ activity and FⅫ antigen of the proband were significantly decreased(＜1 ％ ).The FⅫ activity of his wife,daughter,son and mother was also dropped to about 51％、21％、21％ and 50％,respectively,and so was the FⅫ antigen (42％、32％、37％ and 48％,respectively).Homozygous missense mutation of G→ A transition at position 8699 in exon 14 resulting in Gly542Ser was identified in the proband.His mother,son and daughter were heterozygous for Gly542Ser.In the promoter regions of FⅫgene,the genotype of the proband and the other members was 46T/T.Conclusion Homozygous missense mutation Gly542Ser was found in a pedigree of hereditary F Ⅻ deficiency. The homozygous missense mutation might have resulted from his parents by consanguineous marriage. Gly542Ser and 46T/T have contributed to the pathogenesis of the hereditary factor Ⅻ deficiency pedigree.