摘要
目的针对50个不同临床背景的假肥大型肌营养不良（Duchenne/Becker muscular dystrophy, DMD/BMD）家系，采用多种检测手段建立DMD/BMD的个体化产前诊断方案，降低DMD/BMD的发病率。方法应用多重连接探针扩增技术（multiplex ligation-dependent probe amplification，MLPA）技术对50个DMD/BMD家系先证者进行检测。仅检出单个外显子缺失者采用PCR扩增验证结果准确性；未发现缺失重复者，采用Sanger测序对DMD基因进行测序；检出突变者，对家系女性亲属进行携带者筛查，对怀孕的携带者行绒毛、羊水或脐血穿刺进行产前基因诊断；所有产前诊断标本进行连锁分析，判断是否携带致病单体型，辅助诊断，确保基因诊断结果的准确可靠。产前诊断标本均做母血污染鉴定。结果50个DMD/BMD家系，23例先证者为DMD基因大片段缺失突变，11例为单个外显子的缺失，10例为重复突变，Sanger测序发现5例为外显子编码区的微小突变，1例未查到与疾病发生相关的突变。50个家系中，有37例孕妇要求产前诊断，其中10例胎儿为男性患者，6例为女性携带者，21例胎儿未检测到突变，21例胎儿出生后进行肌酸激酶检测，与产前诊断结果一致。1例家系先证者为第51外显子缺失型，先证者母亲未见异常，胎儿基因型与先证者一致，且先证者与胎儿具有相同单体型。先证者母亲未检出异常，但曾连续生育具有相同缺失型突变的DMD/BMD患儿，提示可能为DMD基因第51外显子缺失突变的生殖腺嵌合体。结论不同临床背景的孕妇，采用多种检测手段不同方案的组合，可以最大限度的降低DMD/BMD患儿的出生，为临床诊治、遗传咨询提供可靠的依据和技术手段。
ObjectiveTo establish individualized prenatal diagnosis program for families affected with Duchenne/Becker muscular dystrophy （DMD/BMD） and different clinical background using a variety of methods.Methods
Multiplex ligation-dependent probe amplification （MLPA） was performed on 50 patients suspected for DMD/BMD. For single exon deletions of the DMD gene, PCR was used for validating the results. For those without any deletion or duplication, Sanger sequencing was used to screen for DMD gene mutations in the children and their mothers. Prenatal genetic testing was provided to female carriers using chorionic villus, amniocentesis or cord blood samples. To ensure the accuracy of diagnosis, all prenatal specimens were also subjected to linkage analysis.Results Among the 50 patients with DMD/BMD, 23 harbored large deletions, 11 only had single exon deletions, 10 harbored duplications, and 5 had small scare mutations. No mutation was detected in one family. For 37 women undergoing prenatal diagnosis, 10 fetuses were identified as affected males, 6 were female carriers, while 21 were not found to carry any mutation. Testing of creatine kinase was consistent with the results of prenatal diagnosis. For a patient harboring exon 51 deletion, the same mutation was found in a fetus but not in their mother. The proband and fetus had inherited the same haplotype, which suggested that the mother probably has germline mosaicism for the mutation.Conclusion
Application of individualized methods for analyzing pregnant women with different clinical background can minimize the risk for giving birth to further children affected with DMD/BMD.
作者
李焕铮
徐晨阳
毛义建
卢金芳
项延包
徐雪琴
唐少华
Li Huanzheng , Xu Chenyang , Mao Yijian , Lu J in fang , Xiang Yanbao , Xu Xueqin , Tang Shaohua(Center of Prenatal Diagnosis, Wenzhou Central Hospital, Wenzhou , Zhejiang 325000, Chin)
出处
《中华医学遗传学杂志》
CAS
CSCD
2018年第2期169-174,共6页
Chinese Journal of Medical Genetics
基金
浙江省医药卫生科技项目（2015KYB363）
温州市科技计划项目（Y20140745,Y20150305）
关键词
假肥大型肌营养不良
产前诊断
多重连接探针扩增技术
生殖腺嵌合
Duchenne/Becker muscular dystrophy
Prenatal diagnosis
Multiplex ligation-dependent probe amplification
Germline mosaicism
