title: Next-generation sequencing discloses a nonsense mutation in the dystrophin gene from long preserved dried umbilical cord and low-level somatic mosaicism in the proband mother.
abstract: Duchene muscular dystrophy (DMD) is a progressive muscle wasting disease, caused by mutations in the dystrophin (DMD) on the X chromosome. One-third of patients are estimated to have de novo mutations. To provide in-depth genetic counseling, the comprehensive identification of mutations is mandatory. However, many DMD patients did not undergo genetic diagnosis because detailed genetic diagnosis was not available or their mutational types were difficult to identify. Here we report the genetic testing of a sporadic DMD boy, who died >20 years previously. Dried umbilical cord preserved for 38 years was the only available source of genomic DNA. Although the genomic DNA was severely degraded, multiplex ligation-dependent probe amplification analysis was performed but no gross mutations found. Sanger sequencing was attempted but not conclusive. Next-generation sequencing (NGS) was performed by controlling the tagmentation during library preparation. A nonsense mutation in DMD (p.Arg2095*) was clearly identified in the proband. Consequently, the identical mutation was detected as an 11% mosaic mutation from his healthy mother. Finally, the proband's sister was diagnosed as a non-carrier of the mutation. Thus using NGS we have identified a pathogenic DMD mutation from degraded DNA and low-level somatic mosaicism, which would have been overlooked using Sanger sequencing.
authors.affiliation: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan.|Division of Genetic Counseling, Kobe University Hospital, Kobe, Japan.
authors.forename: Mariko
authors.initials: M
authors.lastname: Taniguchi-Ikeda
authors.affiliation: Department of Pediatrics, Hyogo College of Medicine, Nishinomiya, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Takeshima
authors.affiliation: Department of Pediatrics, Hyogo College of Medicine, Nishinomiya, Japan.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Lee
authors.affiliation: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan.|Division of Genetic Counseling, Kobe University Hospital, Kobe, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Nishiyama
authors.affiliation: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Awano
authors.affiliation: Nikoniko-house Medical Welfare Center, Kobe, Japan.
authors.forename: Mariko
authors.initials: M
authors.lastname: Yagi
authors.affiliation: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan.
authors.forename: Ai
authors.initials: A
authors.lastname: Unzaki
authors.affiliation: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan.
authors.forename: Kandai
authors.initials: K
authors.lastname: Nozu
authors.affiliation: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan.
authors.forename: Hisahide
authors.initials: H
authors.lastname: Nishio
authors.affiliation: Department of Medical Rehabilitation, Kobegakuin University, Kobe, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Matsuo
authors.affiliation: Division of Molecular Genetics, Institute for Comprehensive Medical Science, Fujita Health University, Aichi, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Kurahashi
authors.affiliation: Division of Genetic Counseling, Kobe University Hospital, Kobe, Japan.|Department of Neurology/Molecular Brain Science, Kobe University Graduate School of Medicine, Kobe, Japan.
authors.forename: Tatsushi
authors.initials: T
authors.lastname: Toda
authors.affiliation: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Morioka
authors.affiliation: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan.
authors.forename: Kazumoto
authors.initials: K
authors.lastname: Iijima
mesh_terms: D000328:Adult; D018389:Codon, Nonsense / Q000235:genetics; D016189:Dystrophin / Q000235:genetics*; D005260:Female; D005312:Fetal Blood; D005820:Genetic Testing; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D008297:Male; D009030:Mosaicism; D020388:Muscular Dystrophy, Duchenne / Q000235:genetics* / Q000473:pathology; D009154:Mutation
chemical_list: D018389:Codon, Nonsense; D016189:Dystrophin