title: Interphase fluorescence in situ hybridization characterization of mosaicism using uncultured amniocytes and cultured stimulated cord blood lymphocytes in prenatally detected Pallister-Killian syndrome.
abstract: OBJECTIVE
  This study aims to present molecular cytogenetic characterization of Pallister-Killian syndrome (PKS).
  
  
  METHODS
  A 37-year-old woman underwent amniocentesis at 18 weeks of gestation. Amniocentesis revealed a karyotype of 47,XY,+i(12)(p10)[6]/48,XY,+i(12)(p10)×2[1]/46,XY[6]. Repeated amniocentesis was performed at 20 weeks of gestation. Array comparative genomic hybridization (aCGH) was performed using uncultured amniocytes, cord blood, and skin. Quantitative fluorescent polymerase chain reaction (QF-PCR) was performed using uncultured amniocytes and parental bloods. Interphase fluorescence in situ hybridization (FISH) analysis was performed using uncultured amniocytes and cultured stimulated cord blood lymphocytes. Conventional cytogenetic analysis was performed using cultured cells from amniotic fluid, skin, placenta, umbilical cord, and cord blood.
  
  
  RESULTS
  Repeated amniocentesis revealed a mosaic tetrasomy 12p level of 25% (10/40), cultured cord blood lymphocytes had no mosaicism, cultured skin fibroblasts had a mosaic tetrasomy 12p level of 52.5% (21/40), umbilical cord fibroblasts had a mosaic tetrasomy 12p level of 72.5% (29/40), and the placental cells had a mosaic tetrasomy 12p level of 2.5% (1/40) on conventional cytogenetics. An aCGH analysis revealed that the increases in gene dosage in 12p for uncultured amniocytes, skin, and cord blood were the log2 ratios of 0.9, 0.7, and 0.7, respectively. Interphase FISH on uncultured amniocytes revealed a mosaic level of 73.1% (49/67) (tetrasomy 12p: 33; hexasomy 12p: 16). Interphase FISH analysis of stimulated cultured cord blood lymphocytes revealed a mosaic level of 58.3% (60/103) (tetrasomy 12p: 51; hexasomy 12p: 9).
  
  
  CONCLUSIONS
  In the diagnosis of PKS by conventional culture cytogenetics, cord blood samplings and placental samplings are prone to a negative result when compared with amniocentesis. Whenever cord blood sampling is applied for prenatal diagnosis of PKS, aCGH on uncultured cord blood or interphase FISH on cultured cord blood can be used for the diagnosis, in addition to conventional cytogenetics.
authors.affiliation: Department of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei, Taiwan; Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan; Department of Biotechnology, Asia University, Taichung, Taiwan; School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung, Taiwan; Institute of Clinical and Community Health Nursing, National Yang-Ming University, Taipei, Taiwan; Department of Obstetrics and Gynecology, School of Medicine, National Yang-Ming University, Taipei, Taiwan. Electronic address: cpc_mmh@yahoo.com.
authors.forename: Chih-Ping
authors.initials: CP
authors.lastname: Chen
authors.affiliation: Department of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei, Taiwan.
authors.forename: Cheng-Ran
authors.initials: CR
authors.lastname: Peng
authors.affiliation: Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan.
authors.forename: Schu-Rern
authors.initials: SR
authors.lastname: Chern
authors.affiliation: Department of Obstetrics and Gynecology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Yu-Ling
authors.initials: YL
authors.lastname: Kuo
authors.affiliation: Gene Biodesign Co. Ltd, Taipei, Taiwan.
authors.forename: Peih-Shan
authors.initials: PS
authors.lastname: Wu
authors.affiliation: Department of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei, Taiwan.
authors.forename: Dai-Dyi
authors.initials: DD
authors.lastname: Town
authors.affiliation: Department of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei, Taiwan.
authors.forename: Chen-Wen
authors.initials: CW
authors.lastname: Pan
authors.affiliation: Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan.
authors.forename: Chien-Wen
authors.initials: CW
authors.lastname: Yang
authors.affiliation: Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan; Department of Bioengineering, Tatung University, Taipei, Taiwan.
authors.forename: Wayseen
authors.initials: W
authors.lastname: Wang
mesh_terms: D000328:Adult; D000649:Amniocentesis; D000650:Amnion / Q000166:cytology*; D002478:Cells, Cultured; D025063:Chromosome Disorders / Q000097:blood / Q000175:diagnosis* / Q000235:genetics; D002881:Chromosomes, Human, Pair 12 / Q000235:genetics; D055028:Comparative Genomic Hybridization; D005260:Female; D005312:Fetal Blood; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008213:Lymphocyte Activation; D008214:Lymphocytes; D009030:Mosaicism; D011247:Pregnancy
keywords: Pallister–Killian syndrome; blood lymphocyte; interphase FISH; mosaic tetrasomy 12p; prenatal diagnosis