title: Successful application of the strategy of blastocyst biopsy, vitrification, whole genome amplification, and thawed embryo transfer for preimplantation genetic diagnosis of neurofibromatosis type 1.
abstract: OBJECTIVE
  Preimplantation genetic diagnosis (PGD) offers an alternative for women to carry an unaffected fetus risk of hereditary diseases. Trophectoderm biopsy may provide more cells for accurate diagnosis. However, the time allowed for transportation of the specimens to the laboratory and performance of molecular diagnosis is limited. We designed a PGD program of trophectoderm biopsy, vitrification of blastocysts, whole genome amplification (WGA), double confirmatory genotypings, and thawed embryo transfer.
  
  
  METHODS
  We conducted this strategy for a woman of familial neurofibromatosis type I (NF-1). She had a genotype of heterozygous c.6709C>T mutation of NF1 gene. Trophectoderm biopsies were performed on 13 blastocysts. Then, individual blastocyst was vitrified. WGA was performed for the samples, followed by genotypings with both real-time polymerase chain reaction and sequencing. Eight embryos were diagnosed as unaffected, four were affected, and one was inconclusive because of allele drop-out. In the next cycle, two unaffected blastocysts were thawed and transferred, that resulted in a singleton pregnancy. The pregnancy was confirmed as unaffected by means of chorionic villi sampling.
  
  
  CONCLUSIONS
  We first demonstrate successful application of blastocyst biopsy, vitrification, WGA, and thawed embryo transfer for PGD of a monogenic disease. Vitrification of blastocysts after biopsy permits sufficient time for shipment of samples and operation of molecular diagnosis.
authors.affiliation: Department of Obstetrics and Gynecology, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Yi-Lin
authors.initials: YL
authors.lastname: Chen
authors.forename: Chia-Cheng
authors.initials: CC
authors.lastname: Hung
authors.forename: Shin-Yu
authors.initials: SY
authors.lastname: Lin
authors.forename: Mei-Ya
authors.initials: MY
authors.lastname: Fang
authors.forename: Yi-Yi
authors.initials: YY
authors.lastname: Tsai
authors.forename: Li-Jung
authors.initials: LJ
authors.lastname: Chang
authors.forename: Chien-Nan
authors.initials: CN
authors.lastname: Lee
authors.forename: Yi-Ning
authors.initials: YN
authors.lastname: Su
authors.forename: Shee-Uan
authors.initials: SU
authors.lastname: Chen
authors.forename: Yu-Shih
authors.initials: YS
authors.lastname: Yang
mesh_terms: D000328:Adult; D001706:Biopsy; D001755:Blastocyst / Q000166:cytology*; D004624:Embryo Transfer; D005260:Female; D055106:Genome-Wide Association Study; D005838:Genotype; D006801:Humans; D008297:Male; D009456:Neurofibromatosis 1 / Q000235:genetics*; D011247:Pregnancy; D011256:Pregnancy Outcome; D019836:Preimplantation Diagnosis / Q000379:methods*; D014327:Trophoblasts / Q000166:cytology; D058989:Vitrification