CAJ | 학술논문

目的分析4个Wiskott-Aldrich综合征家系致病基因WASP基因突变位点,探讨WASP基因分析用于产前诊断的可行性.方法应用PCR扩增后直接双向测序方法,对4个Wiskott-Aldrich综合征家系中3例先证者和4例母亲及100名正常个体的WASP基因的外显子区及侧翼序列进行突变分析,确定致病突变后,对其中2个家系中的高危胎儿进行孕早期产前基因诊断.结果共发现4种WASP基因突变,c.91A ＞G (p.E31K),c.665C ＞T (p.R211X),c.397G＞A(p.E133K),c.952-953 delCC(p.P317fsX18),其中c.952-953delCC为首次报道的突变(novel).家系1中先证者携带WASP基因p.E31K错义突变,母亲未携带相应突变,该家系先证者突变为新生突变;家系2中先证者携带WASP基因p.R211X无义突变,母亲为该突变的杂合携带者;家系3中先证者携带p.E133K错义突变,母亲为相应致病突变的杂合携带者;家系4有家族史但先证者已故,先证者母亲携带c.952-953delCC杂合突变;100名正常个体未检测到上述突变.2个产前诊断家系中胎儿均为男性,家系2中胎儿携带与其先证者相同的突变推测为患者可能性大,胎儿父母选择治疗性引产术后取胎儿流产物标本行基因诊断,结果与产前诊断相同;家系3中胎儿未携带与其先证者相同的突变,生后随访至6个月,新生儿各项检查结果均正常.结论 WASP基因突变是Wiskott-Aldrich综合征4家系的致病原因,c.952-953delCC(p.P317fsX18)为首次报道的新突变,通过产前诊断避免此类患儿出生是目前预防该病发生的有效方法.
목적 분석4개Wiskott-Aldrich종합정가계치병기인WASP기인돌변위점,탐토WASP기인분석용우산전진단적가행성.방법 응용PCR확증후직접쌍향측서방법,대4개Wiskott-Aldrich종합정가계중3례선증자화4례모친급100명정상개체적WASP기인적외현자구급측익서렬진행돌변분석,학정치병돌변후,대기중2개가계중적고위태인진행잉조기산전기인진단.결과 공발현4충WASP기인돌변,c.91A ＞G (p.E31K),c.665C ＞T (p.R211X),c.397G＞A(p.E133K),c.952-953 delCC(p.P317fsX18),기중c.952-953delCC위수차보도적돌변(novel).가계1중선증자휴대WASP기인p.E31K착의돌변,모친미휴대상응돌변,해가계선증자돌변위신생돌변;가계2중선증자휴대WASP기인p.R211X무의돌변,모친위해돌변적잡합휴대자;가계3중선증자휴대p.E133K착의돌변,모친위상응치병돌변적잡합휴대자;가계4유가족사단선증자이고,선증자모친휴대c.952-953delCC잡합돌변;100명정상개체미검측도상술돌변.2개산전진단가계중태인균위남성,가계2중태인휴대여기선증자상동적돌변추측위환자가능성대,태인부모선택치료성인산술후취태인유산물표본행기인진단,결과여산전진단상동;가계3중태인미휴대여기선증자상동적돌변,생후수방지6개월,신생인각항검사결과균정상.결론 WASP기인돌변시Wiskott-Aldrich종합정4가계적치병원인,c.952-953delCC(p.P317fsX18)위수차보도적신돌변,통과산전진단피면차류환인출생시목전예방해병발생적유효방법.
Objective Wiskott-Aldrich syndrome (WAS) is a rare X-linked primary immunodeficiency characterized by microthrombocytopenia,eczema,recurrent infections,and an increased incidence of autoimmunity and malignancies.The patients always have a severe clinical phenotype that can result in death if not diagnosed and treated early in life.The treatment of choice with the best outcome is hematopoietic stem cell transplantation,preferably from a matched related donor.But uncertain treatment effect and high treatment cost limit its clinical application.It is the best strategy that avoiding birth of a fetus with defect through prenatal diagnosis at present.This study aimed to analyze the mutation of WASP gene in 4 Chinese families with WAS and to provide prenatal diagnosis for the high-risk fetus.Method The probands of the four WAS families were all males,one of whom was deceased but had a family history and clinical datas integrated.All the patients were detected with blood routine tests,immunological tests and bone marrow examination.PCR and bilateral direct sequencing of PCR product was carried out in the regions of exon and exon-intron boundaries of WASP gene for 3 probands,4 mothers and 100 unrelated healthy individuals as control Prenatal diagnosis was provided for the two fetuses at the first trimester by mutation analysis.Result Four WASP gene mutations were detected:c.91A ＞ G (p.E31 K),c.665C ＞ T (p.R211X),c.397G ＞ A (p.E133K),c.952-953delCC (p.P317fsX18),among which c.952-953delCC (p.P317fsX18) was first reported.Mothers in Family 2,3 and 4 were carriers of WASP gene mutation,but family 1 was considered as a de-novo mutation.None of the 100 unaffected subjects had the above mutants.Prenatal diagnosis indicated that the fetus in family 2 was male and carried the same mutation as the proband,so the fetus was presumably to be a patient.The parents decided to receive an induced abortion.Following the termination of the pregnancy,the result of gene analysis of the aborted tissues was consistent with prenatal diagnosis.The fetus in family 3 was normal male confirmed by normal test results six months after birth.Conclusion The 4 mutations of the WASP gene probably were causative to the families of WAS,among which c.952-953delCC was reported for the first time.Prenatal diagnosis by DNA sequencing is the effective method to avoid birth of WAS patient.