假肥大型肌营养不良性腺嵌合体七个家系的遗传学分析及生殖干预  

Genetic analysis and reproductive intervention of 7 families with gonadal mosaicism for Duchenne muscular dystrophy

作　　者：高伯笛 杨晓文 胡晓 何文斌 赵晓蒙 龚斐 杜娟[1,2] 张前军 卢光琇[1,2,3] 林戈 李汶[1,2] Gao Bodi;Yang Xiaowen;Hu Xiao;He Wenbing;Zhao Xiaomeng;Gong Fei;Du Juan;Zhang Qianjun;Lu Guangxiu;Lin Ge;Li Wen(CITIC Xiangya Reproductive and Genetic Hospital,Hunan Provincial Reproductive and Genetic Clinical Medical Research Center,Changsha,Hunan 410078,China;National Engineering Research Center for Human Stem Cells,Changsha,Hunan 410013,China;Research Center,Changsha,Hunan 410078,China)

机构地区：[1]中信湘雅生殖与遗传专科医院·湖南省生殖与遗传临床医学研究中心,长沙410078 [2]中南大学生殖与干细胞工程研究所,长沙410078 [3]人类干细胞国家工程研究中心,长沙410013

出　　处：《中华医学遗传学杂志》2023年第4期423-428,共6页Chinese Journal of Medical Genetics

基　　金：中国博士后科学基金(2022M711119);湖南创新型省份建设专项基金(2019SK4012)。

摘　　要：目的探讨7个假肥大型肌营养不良(DMD)性腺嵌合体家系的遗传学病因。方法选择2014年9月至2022年3月就诊于中信湘雅生殖与遗传专科医院的7个DMD性腺嵌合体家系为研究对象。收集家系的临床资料,应用胚胎植入前单基因遗传学检测(PGT-M)对家系6先证者的母亲进行助孕,采集7个家系的先证者、先证者母亲及其他患者的外周静脉血样、家系1~4胎儿的羊水、家系6体外培养胚胎的细胞,提取基因组DNA,用多重连接探针扩增(MLPA)对DMD基因进行检测,对家系1~3、5~6先证者、其他患者、胎儿、体外培养胚胎进行基于短串联重复序列(STR)/单核苷酸多态性(SNP)的单体型分析。结果MLPA检测结果显示,家系1~4、5、7的先证者与胎儿/先证者弟弟存在相同的DMD基因变异,其母亲DMD基因均未见异常;家系6的先证者仅与1枚体外培养胚胎(共9枚)存在相同的DMD基因变异,其母亲与通过PGT-M成功助孕胎儿的DMD基因均未见异常。STR单体型分析结果显示家系1~3、5的先证者与胎儿/先证者弟弟均遗传了相同的母源X染色体;SNP单体型分析结果显示,家系6先证者仅与1枚体外培养的胚胎(共9枚)继承了相同的母源X染色体。家系1胎儿与家系6中PGT-M助孕成功胎儿出生后随访均健康,家系2~3先证者的母亲选择了引产。结论基于STR/SNP的单体型分析是判断性腺嵌合体的有效方法,对生育过DMD基因变异患儿而外周血基因型正常的女性应考虑性腺嵌合体风险,再次妊娠时建议进行产前诊断与生殖干预,避免缺陷患儿的出生。Objective To explore the genetic basis for 7 families with gonadal mosaicism for Duchenne muscular dystrophy(DMD).Methods For the 7 families presented at the CITIC Xiangya Reproductive and Genetic Hospital from September 2014 to March 2022,clinical data were collected.Preimplantation genetic testing for monogenic disorders(PGT-M)was carried out for the mother of the proband from family 6.Peripheral venous blood samples of the probands,their mothers and other patients from the families,amniotic fluid samples from families 1~4 and biopsied cells of embryos cultured in vitro from family 6 were collected for the extraction of genomic DNA.Multiplex ligation-dependent probe amplification(MLPA)was carried out for the DMD gene,and short tandem repeat(STR)/single nucleotide polymorphism(SNP)-based haplotypes were constructed for the probands,other patients,fetuses and embryos.Results The results of MLPA showed that the probands and the fetuses/probands′brothers in families 1~4,5,7 had carried the same DMD gene variants,whilst the probands′mothers were all normal.The proband in family 6 carried the same DMD gene variant with only 1 embryo(9 in total)cultured in vitro,and the DMD gene of the proband′s mother and the fetus obtained through the PGT-M were normal.STR-based haplotype analysis showed that the probands and the fetuses/probands′brothers in families 1~3 and 5 have inherited the same maternal X chromosome.SNP-based haplotype analysis showed that the proband from family 6 has inherited the same maternal X chromosome with only 1 embryo(9 in total)cultured in vitro.The fetuses in families 1 and 6(via PGT-M)were both confirmed to be healthy by follow up,whilst the mothers from families 2 and 3 had chosen induced labor.Conclusion Haplotype analysis based on STR/SNP is an effective method for judging gonad mosaicism.Gonad mosaicisms should be suspected for women who have given births to children with DMD gene variants but with a normal peripheral blood genotype.Prenatal diagnosis and reproductive intervention may

关 键 词：杜氏肌营养不良 性腺嵌合体 DMD基因 多重连接探针扩增 单体型分析 

分 类 号：R746.2[医药卫生—神经病学与精神病学]