title: Spinal muscular atrophy patient detection and carrier screening using dried blood spots on filter paper.
abstract: OBJECTIVE
  Spinal muscular atrophy (SMA) is a common autosomal recessive neuromuscular disorder. It is caused by mutations in the SMN1, and its clinical severity is modified by copy number variations of the SMN2. According to previous studies, deletion of SMN1 exon 7 is the most frequently observed in patients with SMA. Therefore, molecular analyses exploiting this genetic lesion could be beneficial in the diagnosis of SMA. Unfortunately, in many geographical regions, physicians do not have the latest molecular screening technologies at their immediate disposal. Thus, to overcome this issue, we developed an SMA-diagnosing system using dried blood spots (DBS) placed on filter paper to facilitate remote diagnosis.
  
  
  METHODS
  In this study, we validate the applicability of DBS on Flinders Technology Associates (FTA) filter paper for detecting SMN1 exon 7 deletions and copy number variations of SMN1 and SMN2. To detect exon 7 deletions in SMN1, polymerase chain reaction (PCR)-restriction fragment length polymorphism analysis was conducted by using DNA extracted from the DBS on FTA filter paper that had been stored at room temperature for a period of up to 4 years. To determine the copy numbers of SMN1 and SMN2, we carried out SYBR green-based real-time PCR by using the same blood specimens.
  
  
  RESULTS
  The results obtained from the DBS on FTA filter paper were in complete concordance with those analyses using fresh blood specimens. This indicates that DBS on filter papers is a reliable method for SMA patient detection and carrier screenings.
  
  
  CONCLUSIONS
  The SMA-diagnosing system, combined with the mailing of DBS on filter paper, will be beneficial for patients suffering from neuromuscular disorders in areas with limited or no access to diagnostic facilities with molecular capabilities.
authors.affiliation: Division of Genetic Epidemiology, Department of Community Medicine and Social Healthcare Science, Kobe University Graduate School of Medicine, Kobe, Japan. iin_999@yahoo.com
authors.forename: Nur Imma Fatimah
authors.initials: NI
authors.lastname: Harahap
authors.forename: Indra Sari Kusuma
authors.initials: IS
authors.lastname: Harahap
authors.forename: Richard Hideki
authors.initials: RH
authors.lastname: Kaszynski
authors.forename: Dian Kesuma Pramudya
authors.initials: DK
authors.lastname: Nurputra
authors.forename: Tri Budi
authors.initials: TB
authors.lastname: Hartomo
authors.forename: Huyen Thi Van
authors.initials: HT
authors.lastname: Pham
authors.forename: Tomoto
authors.initials: T
authors.lastname: Yamamoto
authors.forename: Satoru
authors.initials: S
authors.lastname: Morikawa
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Nishimura
authors.forename: Imam
authors.initials: I
authors.lastname: Rusdi
authors.forename: Retno
authors.initials: R
authors.lastname: Widiastuti
authors.forename: Hisahide
authors.initials: H
authors.lastname: Nishio
mesh_terms: D001800:Blood Specimen Collection / Q000295:instrumentation / Q000379:methods*; D002648:Child; D002675:Child, Preschool; D059788:Dried Blood Spot Testing; D005091:Exons / Q000235:genetics; D005260:Female; D018628:Gene Dosage / Q000235:genetics; D006580:Genetic Carrier Screening / Q000379:methods*; D005820:Genetic Testing / Q000379:methods*; D006801:Humans; D007223:Infant; D008297:Male; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods; D012680:Sensitivity and Specificity; D017384:Sequence Deletion; D014897:Spinal Muscular Atrophies of Childhood / Q000175:diagnosis* / Q000235:genetics; D055533:Survival of Motor Neuron 1 Protein / Q000235:genetics*; D055540:Survival of Motor Neuron 2 Protein / Q000235:genetics
chemical_list: C526471:SMN1 protein, human; C526477:SMN2 protein, human; D055533:Survival of Motor Neuron 1 Protein; D055540:Survival of Motor Neuron 2 Protein