Preimplantation Genetic   Diagnosis (PGD)

go to an Information sheet for our OHSU (PGD) Patients

We are the first and only comprehensive preimplantation genetic diagnosis (PGD) program in the Northwest United States. We provide this service for women who:

• are over 35 years old and therefore at an increased  risk of chromosome problems (e.g.. Down Syndrome)
• have experienced recurrent pregnancy loss
• have experienced unexplained IVF failure
• are at risk of transmitting X-linked or single gene disorders such as:
• Cystic fibrosis
• Lesch Nyhan
• Tay Sachs
• Huntington's disease
• Myotonic dystrophy
• Spinal cerebellar ataxia
• Spinal muscular atrophy-1 (SMA-1)
• Duchenne muscular dystrophy
• VCFS/DiGeorge syndromes
• Fanconi anemia-A
• SCIDS (autosomal recessive mutation of ADA)
• Hemophilia A
• RH incompatibility
• Human Platelet Antigen (PLA-1)

1. Day 3 embryo (6-10 cell stage).		2. The blastomere biopsy showing an isolated blastomere to be analyzed.

Preimplantation genetic diagnosis (PGD) is now available as a clinical service to patients participating in the OHSU In vitro Fertilization (IVF) Program. PGD combines the existing technology of IVF and micromanipulation (ICSI, embryo biopsy) with molecular genetic techniques used in clinical practice and allows the selection of normal embryos for transfer thereby reducing the possibility of establishing an abnormal pregnancy. Currently, the program offers diagnosis of certain chromosome abnormalities prior to implantation for patients at high risk. In addition, testing is being developed for patients at risk of transmitting X-linked disorders, autosomal gene defects, and chromosomes translocations.

Many women in IVF programs are over 35 years old and at an increased risk for chromosomal abnormalities, particularly aneuploidy resulting during meiosis or initial cleavage. The age related risk of common aneuploidies (chromosomes 13, 15, 16, 17, 18, 21,  22,  X and Y) has not only become an indication for PGD, but the most common application, accounting for more than 60% of PGD cycles performed. Thus, by identifying abnormal embryos and transferring only chromosomally normal embryos, implantation rates should increase while spontaneous abortions and trisomic pregnancies should decrease. In addition, PGD may prove useful in the investigation of unexplained IVF failures in young patients. Dual and multicolor fluorescent in situ hybridization (FISH) technology uses specific probes for chromosomes (e.g. 13, 15, 16, 17, 18, 21,  22, X and Y) to assess the number of copies of these chromosomes. A region specific chromosome 22 probe is also available for use in early diagnosis of common micro deletions, such as the long arm deletion of chromosome 22 leading to VCFS/DiGeorge syndromes. 

Recent advances in DNA diagnostic techniques also allow detection of autosomal dominant and recessive disorders such as cystic fibrosis, Tay Sachs, Lesch Nyhan, Huntington disease, myotonic dystrophy, spinal muscular atrophy or Duchenne muscular dystrophy. DNA analysis using PCR based methods such as multiplex, nested or fluorescent PCR can detect the presence of a mutation in the affected gene of the embryos produced by IVF.  Learn more at  Genesis Genetics a leading PGD provider.
 

3. Fluorescence in situ hybridization (FISH): Normal female carrying 2 copies for chromosomes 13, 18 , 21, and X.

4. Fluorescence in situ hybridization (FISH): Male monosomic 18: This affected male is missing a copy of chromosome 18. ( Y chromosome is yellow)

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Feel free to contact Nadia Ouhibi Ph.D. (ouhibin@ohsu.edu) directly with any questions concerning PGD.

Recommended Links:

Genesis Genetics is the leading provider of Preimplantation Genetic Diagnosis (PGD) - providing expert laboratory services for many of the most respected in vitro fertilization (IVF) centers across the country and throughout the world.

 www.Geneforum.org
 . . .  "a new nonprofit organization, enables citizens to confront advancements in genetic research and technology, to understand the science behind them, and to address important ethical, legal, and social questions."