Huanhuan Wang1,2, Yan Xu1,2, Xiaoqing Liu2,3, Lei Wang4, Wenting Jiang1,2, Bing Xiao1,2, Wei Wei1,2, Yingwei Chen1,2, Weiping Ye1,4, Xing Ji1,2. 1. Prenatal Diagnosis Center, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China. 2. Department of Genetics, Shanghai Institute of Pediatric Research, Shanghai, China. 3. Department of Pediatric Neurology, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China. 4. Department of Obstetrics, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Abstract
OBJECTIVES: The objective of this study is to report 6-year clinical prenatal diagnosis experience of Duchenne muscular dystrophy (DMD)-affected families evaluated at a single prenatal diagnosis center in China and establish a reliable and rational prenatal diagnosis procedure for DMD families. METHODS: The prenatal diagnosis data of 146 at-risk pregnancies in 131 DMD families referred to our center from 2010 to 2016 were retrospectively reviewed. RESULTS: The mutation detection rate of the probands was greater than 99%. In the 131 families, 50 mothers showed negative results during carrier testing, and de novo exon deletions arose in 51.1% of the probands. Of the 146 pregnancies, 91 were male fetuses, 34 of which were affected. Germline mosaicism was identified three times in this cohort, and recombination of the DMD gene was detected in nine cases. CONCLUSIONS: Accurate genetic diagnosis of the proband is important for preventing recurrence in at-risk families. The present results demonstrate the importance of considering maternal germline mosaicism in the genetic assessment. Prenatal diagnosis should be suggested to the parent with a DMD proband whether carrier testing found the causative mutation in the mother's blood or not. Finally, we have developed a prenatal diagnosis algorithm for dystrophinopathies that combines multiplex ligation-dependent probe amplification, quantitative PCR, sequencing and linkage analyses.
OBJECTIVES: The objective of this study is to report 6-year clinical prenatal diagnosis experience of Duchenne muscular dystrophy (DMD)-affected families evaluated at a single prenatal diagnosis center in China and establish a reliable and rational prenatal diagnosis procedure for DMD families. METHODS: The prenatal diagnosis data of 146 at-risk pregnancies in 131 DMD families referred to our center from 2010 to 2016 were retrospectively reviewed. RESULTS: The mutation detection rate of the probands was greater than 99%. In the 131 families, 50 mothers showed negative results during carrier testing, and de novo exon deletions arose in 51.1% of the probands. Of the 146 pregnancies, 91 were male fetuses, 34 of which were affected. Germline mosaicism was identified three times in this cohort, and recombination of the DMD gene was detected in nine cases. CONCLUSIONS: Accurate genetic diagnosis of the proband is important for preventing recurrence in at-risk families. The present results demonstrate the importance of considering maternal germline mosaicism in the genetic assessment. Prenatal diagnosis should be suggested to the parent with a DMD proband whether carrier testing found the causative mutation in the mother's blood or not. Finally, we have developed a prenatal diagnosis algorithm for dystrophinopathies that combines multiplex ligation-dependent probe amplification, quantitative PCR, sequencing and linkage analyses.